Contamination load sensing device

ABSTRACT

Systems and methods for bacterial load sensing devices are disclosed. An example contamination sensing device may comprise a body, a light emitter disposed on the body and configured to emit an excitation wavelength of light toward a surface, a sensor disposed on the body, configured to detect light, and directed toward the surface, and a filter adjuster configured to determine, based on the excitation wavelength of light, a filter configured to remove light outside of an emission wavelength range, wherein the emission wavelength range corresponds to wavelengths of light emitted by contamination upon exposure to the excitation wavelength of light, and adjustably move the filter in front of the sensor.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the benefit of U.S. Provisional Application No.62/826,198, titled “Bacterial Load Sensing Device” and filed on Mar. 29,2019. The above-referenced application is hereby incorporated byreference in its entirety.

TECHNICAL FIELD

Aspects of the present disclosure generally relate to processes,systems, and apparatus for bacterial load sensing.

BACKGROUND

Many industries may desire a method and/or device capable of providingreal time surface contamination (e.g., bacterial load) detection. Thereare limited existing solutions on the market that are able to measurebacterial load, also known as bioburden. Many existing methods formeasuring bacterial load are not real time and/or require human input.Industries, such as the healthcare industry, are held responsible forcontamination management, e.g., due to a high bacterial load. Pathogeniccontamination can lead to hospital acquired infections (HAIs) which costhospitals across the United States billions of dollars each year. Otherindustries, such as the pharmaceutical industry and food processingindustry, are held to strict regulations in regards to contamination ofpharmaceuticals and food products and may benefit from additionalbacterial load detection. Many current cleaning, disinfection, andsanitation methods are blind in the sense that the location of high riskcontamination areas are typically unknown beyond obvious tells (e.g.,visible contamination and/or perceivable odor). This may lead toineffective cleaning protocols which may be greatly problematic whenattempting to mitigate hospital acquired infections in healthcaresettings or preventing contamination leading to illness outbreaks inpreparing pharmaceuticals or food products.

SUMMARY

The following presents a simplified summary in order to provide a basicunderstanding of some aspects of the disclosure. The summary is not anextensive overview of the disclosure. It is neither intended to identifykey or critical elements of the disclosure nor to delineate the scope ofthe disclosure. The following summary merely presents some concepts ofthe disclosure in a simplified form as a prelude to the descriptionbelow.

An example contamination sensing device may comprise a body, a lightemitter disposed on the body and configured to emit an excitationwavelength of light toward a surface, a sensor disposed on the body,configured to detect light, and directed toward the surface, and afilter adjuster configured to determine, based on the excitationwavelength of light, a filter configured to remove light outside of anemission wavelength range, wherein the emission wavelength rangecorresponds to wavelengths of light emitted by contamination uponexposure to the excitation wavelength of light, and adjustably move thefilter in front of the sensor.

An example contamination sensing system may comprise a light emittingdevice configured to emit an excitation wavelength of light toward asurface, a light detecting device, in communication with the lightemitting device, comprising a sensor configured to detect light anddirected toward the surface, and a filter adjuster configured todetermine, based on the excitation wavelength of light, a filterconfigured to remove light outside of an emission wavelength range,wherein the emission wavelength range corresponds to wavelengths oflight emitted by contamination upon exposure to the excitationwavelength of light, and adjustably move the filter in front of thesensor.

An example contamination sensing device may comprise a body, at leastone light emitter disposed on the body and configured to emit a lightcomprising an excitation wavelength toward a surface, and a plurality ofsensors disposed on the body and directed toward the surface, whereineach sensor of the plurality of sensors is configured to detect adifferent emission wavelength corresponding to respective wavelengths oflight emitted by contamination upon exposure to the emitted light.

The foregoing and other features of this disclosure will be apparentfrom the following description.

BRIEF DESCRIPTION OF THE DRAWINGS

Examples herein will be described in detail, with reference to thefollowing figures, wherein like designations denote like elements.

FIGS. 1A-1B illustrate an example contamination sensing device.

FIG. 2 illustrates an example contamination sensing device and targetsurface.

FIG. 3 illustrates an example mounted contamination sensing device.

FIGS. 4A-4B illustrate an example enclosure with an contaminationsensing device.

FIGS. 5A-5B illustrate an example enclosure with an contaminationsensing device with a photodiode array.

FIGS. 6A-6B illustrate an example enclosure with an contaminationsensing device with a photodiode array and a lighting element array.

FIG. 7 illustrates an example contamination sensing device and adisinfecting light fixture.

FIG. 8 illustrates an example process for using an contamination sensingdevice.

FIG. 9 illustrates an example contamination map showing levels ofcontamination load.

FIG. 10 illustrates a flow chart for an example contamination sensingdevice creating a bacterial load image.

FIG. 11 illustrates an example system comprising a contamination sensingdevice, processor, and user interface.

FIG. 12 illustrates an example system comprising a contamination sensingdevice and control system.

FIG. 13 illustrates an example two dimensional array of photodiodes.

FIG. 14 illustrates an example one dimension array of photodiodes.

FIG. 15 illustrates an example array of pixels for a fluorescence imagefrom a contamination sensing device.

FIGS. 16A-16C illustrate sensors and/or filters for a contaminationsensing device.

FIG. 17 illustrates a flow chart for using the example contaminationsensing device to detect contamination.

FIG. 18 illustrates a flow chart for binary threshold bioburden levelsorting data from a camera.

FIG. 19 illustrates a flow chart for binary threshold bioburden levelsorting data from a photodiode.

FIG. 20 illustrates a flow chart for bioburden level sorting data from acamera by emission color.

FIG. 21 illustrates a flow chart for bioburden level sorting data from amultispectral/spectrometer sensor by emission spectra.

FIG. 22 illustrates an example computing device for implementing theflowcharts of FIGS. 8, 10, and 17-21 .

DETAILED DESCRIPTION

In the following description of the various examples, reference is madeto the accompanying drawings, which form a part hereof, and in which isshown by way of illustration, various examples that may be practiced. Itis to be understood that other examples may be utilized.

Disinfecting lighting systems (e.g., antimicrobial lighting systems)utilizing safe visible light have been deployed in many marketsincluding healthcare, pharmaceuticals, food service, horticulture,hospitality, residential, and more. Disinfecting lighting systems may beable to provide an intensity of disinfecting energy sufficient forinactivating microorganisms (e.g., bacteria). Although thesedisinfecting lighting fixtures and the lighting layouts of the roomsdisinfecting lighting fixtures may be installed in are often designed toproduce the required intensity on surfaces to inactivate microorganismson those surfaces, there are limited feedback methods to prove that thedisinfecting lights are working.

In healthcare environments there may be a desire for a real timedisinfection validation tool to indicate if disinfection methods reducepathogens on surfaces. Hospital acquired infections (HAI) are asignificant issue. Hospital acquired infections may occur from thetransmission of microorganisms from direct contact with other humans orintake of microorganisms from the environment. During an HAI outbreak, ahospital may use traditional methods to test a surface for pathogenicbacteria, such as, for example, surface swabbing and a bacteria culturetest. Although cleaning, disinfection, and/or sterilization practicesmay be put into place, it may be difficult to appropriately direct thoseresources within allotted times. Manual cleaning may be extremely costlyin terms of materials and labor, and may be prone to human error.Healthcare settings may benefit greatly from identification of high riskareas for harmful microorganisms. Identification of high risk areas mayallow for directing disinfection efforts through, for example, manualcleaning or disinfecting lighting. A real time or near real time methodfor testing environmental surfaces for contamination, such as, forexample, bacteria, pathogens, microorganisms, grease, organic matter,non-organic matter, etc., may be helpful to prevent outbreaks, indicatewhen cleaning is needed, or otherwise indicate when a surface iscontaminated. For example, processes for bacterial load detection may bepartially or fully automated and may determine bacterial loads withinminutes.

Industries such as pharmaceutical and food processing industries mayface strict regulations to prevent the outbreak of illness caused bycontaminated goods and/or surfaces. Characterization of bacterial loadfor non-human goods and/or surfaces, such as, for example, pre or postprocessed food products, medicine, and/or live agriculture may helpmanage contamination that may lead to disease (e.g., food borneillnesses).

As illustrated in FIGS. 1A-1B, a contamination sensing device 100 maycomprise an excitation light source(s) 102 and a sensor(s) 104. Thecontamination sensing device 100 may integrate with additionalprocessors (e.g., processors of FIGS. 11, 12, 22 ), control systems(e.g., control system of FIG. 12 ), and/or computer vision algorithms tocomplete all of its functions. The contamination sensing device 100 mayalso comprise an additional camera configured to capture light in thevisible light spectrum. The contamination sensing device 100 may behoused in a variety of different manners wherein the components of thecontamination sensing device 100 are coupled together, as shown in FIG.1A or physically separate as shown in FIG. 1B.

The excitation light source 102 may comprise, for example, an LED, anarray of LEDs, a laser, an array of lasers, a vertical cavity surfaceemitting laser (VCSEL), or an array of VCSELs. Other light emitters thatmay be used as excitation light source(s) 102 may include, for example,any emitter capable of emitting ultraviolet light including LEDs,fluorescent lamps without phosphor coatings, xenon arc lamps, mercuryvapor, short-wave UV lamps made with fused quartz, black lights(fluorescent lamp coated with UVA emitting phosphor), amalgam lamps,natural or filtered sunlight, incandescent lamps with coatings thatabsorb visible light, gas-discharge (argon, deuterium, xenon,mercury-xenon, metal-halide, arc lamps), halogen lamps with fusedquartz, excimer lamps, etc. In some examples, an LED emitter maycomprise at least one semiconductor die and/or at least onesemiconductor die packaged in combination with light convertingmaterials. In some examples, the excitation light source(s) 102 may befitted with optical components that may alter the path of the excitationlight. (e.g., focus the light into a beam).

FIG. 1A provides an example contamination sensing device 100 where thesensor(s) 104 and the excitation light source(s) 102 are coupledtogether and FIG. 1B provides an example where the excitation lightsource(s) 102 and the sensor(s) 104 are physically separated. In someexamples, the sensor(s) 104 may be mounted on the ceiling and configuredfor a top-down, bird's eye view of the space, which may allow for easierimage capture and mapping to real space locations/coordinates. Thesensor(s) 104 may be located directly above the surface of interest. Theexcitation light source(s) 102 may be mounted separately, for example,in the corner of a room, at any angle (e.g., 90 degrees) from thesensor(s) 104 which may reduce the amount of incident light hitting thesensor(s) 104. Reduction of stray light from the excitation lightsource(s) 102 or any other light producing source may allow thesensor(s) 104 to take a more accurate reading. A reduction in noisecaused by ambient light may result in a clearer fluorescence signal fromthe microorganisms and/or bacterial load. In some examples, such aswhere the excitation light source(s) 102 and sensor(s) 104 arephysically coupled, as shown in FIG. 1A, a dichroic filter may be usedand/or mounted at an angle to reflect the excitation light towards atarget surface, while optimally only transmitting the fluorescencewavelengths to be measured.

In some examples, bacterial load (e.g., contamination on surfaces withinan indoor and/or outdoor space) may be detected, measured, and/orcharacterized by the contamination sensing device 100. Detection maycomprise determining whether a surface is contaminated (e.g., highlevels of bacteria, chemical residue, presence of microorganisms, etc.).In some examples, contamination may be determined by the contaminationsensing device 100 determining that a bacterial load exceeds a thresholdlimit, at which point the surface may be considered contaminated.Measurement may comprise identifying high risk areas (e.g., identifyingwhere bacteria are located) and determining levels of bacteria on thesurface (e.g., where bacteria are most concentrated/dense).Characterization may comprise determining types of microorganisms (e.g.,bacteria) present on the surface. Data may be provided for use by acontrol system integrated with disinfecting light fixture(s) or adisinfecting lighting system and/or provided to a user through a userinterface. A user may be able to make recommendations, based on thebacteria concentration, for directing manual cleaning to high riskareas. Verification may be provided for disinfection through storingdata over time to show trends in bacteria locations and measured surfacebacterial load. A real time method may be provided for determining ifdisinfecting techniques (e.g., disinfecting lighting system ortraditional chemical cleaners) are working.

An example method for measuring bacterial load may utilize an oxygendepletion sensor. Oxygen depletion sensors may detect very small changesin oxygen and create oxygen profiles that may reflect microbial growthin order to determine microbial contamination. The Oxygen depletionmethod may be most applicable to measuring contamination in the air.Oxygen depletion may be used for surface monitoring but, in someexamples, may require a user to swab a surface and place the swab into avial containing fluorescent 02 sensitive polymers that will react to thedepletion of oxygen due to the bacteria growth. The depleted oxygen(e.g., oxygen consumed by the bacteria) may correlate to a microbialload. The time it takes from swabbing to determining results, measuredin colony forming units (CFUs), may, in some examples, take severalhours and therefore may not be real time or instantaneous. Some examplesmay operate in real time or near real time (e.g., within minutes),allowing users and/or system to utilize the data collected nearlyinstantaneously. Some examples of oxygen depletion sensors may require aperson to take a sample of a surface, and may not provide real time ornear real time operation. In some examples, the contamination sensingdevice 100 may not require any human intervention to take themeasurements. The contamination sensing device 100 may work in thebackground with minimal to no extra effort from a user.

Another example method for measuring bacterial load utilizes an ATPmeter or luminometer. ATP meters or luminometers measure AdenosineTriphosphate (ATP) molecules which may correlate to the cleanliness of asurface/water. ATP meters take measurements in relative light units(RLU) based on the bioluminescence of ATP created from the addition ofluciferase enzyme to convert ATP into adenosine monophosphate. Theaddition of luciferase enzyme to convert ATP into adenosinemonophosphate may result in the emission of light. An ATP meterquantifies the emission of light in RLUs which may be proportional tothe amount of ATP in a sample. ATP meters require human intervention totake the measurements. For example, a user is required to swab a desiredsurface and place a sample from the swab within the ATP meter analysis.Some studies have shown there may not be a direct correlation betweenRLU and actual microbial counts which may decrease the reliability ofsurface contamination detection. Some studies have shown that chemicalsurface cleaners with active ingredients such as isopropyl alcohol,citric acid, sodium hypochlorite, etc., may interfere with the analysisof a sample by an ATP meter. In high risk areas, such as healthcarespaces, disinfectants may be used often, making ATP meters unreliable asa source of measuring surface contamination. Another study analyzedseveral different ATP meters and found poor detection and linearity withswabbing surfaces. Surface swabs may be unreliable at picking up thetotal surface ATP. ATP meters also require a minimum concentration ofbacteria to make a measurement, and therefore may not be used forsurfaces with low concentrations of bacteria. Due to these limitations,ATP meters are an unreliable method for measuring surface contamination.

An example method for measuring bacterial load comprises bacterialculture tests. Bacterial culture tests are manually intensive. Bacterialculture tests provide a measure of bacteria count measured in CFUs.Bacterial culture tests rely on a person taking a sample of a surfaceand allowing the cultures within the sample to cultivate. The results ofbacterial culture tests are only as reliable as the sample taken.Bacterial culture tests may not provide accurate information if the mostrepresentative surface is not sampled. Studies have shown that oncebacteria have adhered to a surface they may become more difficult toremove, thus decreasing test accuracy. Once a surface sample is taken,bacterial culture tests requires time for bacteria to grow after beingdeposited in a special medium. Bacterial growth may take several daysbefore the bacterial culture test provides viable information. Bacterialculture test are a labor intensive and time consuming option for surfacecontamination testing. Bacterial culture tests require extensive labequipment and therefore may often not be completed within the spacebeing tested. Instead, bacterial culture samples may be sent to a laband require several days to perform.

The contamination sensing device 100 may be configured to detect,measure, map the locations of, and/or characterize microorganisms withina space. The contamination sensing device 100 may detect and/or measurelevels of bacteria, microorganisms, microbes, yeast, mold, fungi, and/orcontamination in a space. The contamination sensing device 100 may notrequire human intervention or performance of any special tasks, such asgrowing the bacteria from a sample, to take measurements. Thecontamination sensing device 100 may operate without chemical reactionsand therefore may minimize procedural complications. Another advantageof the contamination sensing devices 100 comprises algorithmicallydetermining whether chemical cleaners have been used on surfaces, whichmay cause interference with measurements, and eliminating suchinterference. In some examples, the contamination sensing device maydetermine areas that have been cleaned by chemical cleaners. Thecontamination sensing device 100 may determine areas that have beencleaned, for example, by measuring fluorescence emitted by residue fromchemical cleaners. In some examples, the contamination sensing device100 may flag areas that have not been cleaned. In some examples, thecontamination sensing device 100 may indicate, to a user, areas thathave not been cleaned. In some examples, the contamination sensingdevices disclosed herein may work in real time or near real time (e.g.,within minutes) to provide instant or near instant feedback to users. Insome examples, all or a majority of the physical components of thecontamination sensing device may be contained in the space beingmeasured. In some examples, the contamination sensing device may work onan interior room scale.

In some examples, the excitation light source(s) 102 may emit anexcitation light that may cause microorganisms (e.g., bacteria,contamination, etc.) to fluoresce. Fluorescence may be caused byabsorption of a first wavelength which may cause a second longerwavelength to be emitted. This fluorescence may be referred to asautofluorescence, as the microorganisms themselves may be fluorescingwithout additional exogenous photosensitizers. Autofluorescence may bemeasured by the sensor(s) 104 designed to detect the wavelengths emittedby microorganisms. In some examples, cleaners with photosensitizers maybe used to increase the fluorescence of bacterial contamination. Thecontamination sensing device 100 may be in communication with a databaseof excitation and/or emission spectra of various bacteria/microorganismssuch that measured/observed fluorescence may be compared against thedatabase to identify bacteria/microorganism types. The contaminationsensing device 100 may be in communication with a database of excitationand/or emission spectra of chemicals and/or other nonorganic materials.

Different types of microorganisms (e.g., bacteria) may fluoresce atdifferent wavelengths. The contamination sensing device 100 may usefluorescing color (e.g., using color filtering and threshold matching tothat color) to classify bacteria into categories. In some examples, acontamination sensing device 100 may determine that a measurement doesnot contain a certain bacteria type because a surface does not emit thecorresponding wavelength(s). In some examples, a contamination sensingdevice 100 may determine a measurement does contain a certain bacteriatype because the surface does emit the corresponding wavelength(s).

In some examples, an excitation light may be emitted by the excitationlight source(s) 102 and may be a specific wavelength. In some examples,the excitation wavelength may be a range of wavelengths. In someexamples, the excitation light may be UV (e.g., UV-A aroundapproximately 365 nanometers (nm)) or visible/near UV (e.g., 405 nm). Insome examples, the excitation wavelength used may be between 300 nm and500 nm. In some examples, the excitation wavelength or wavelength rangemay be between 300 nm and 400 nm. In some examples, the excitationwavelength used may be between 350 nm and 380 nm. In some examples, theexcitation wavelength used may be between 380 nm and 420 nm. In someexamples, the excitation wavelength or wavelength range may be between200 nm and 350 nm. In some examples, the excitation wavelength may beapproximately 230 nm and/or approximately 280 nm, for example, toinitiate the autofluorescence of tryptophan, which may be found in manybacteria. In some examples, multiple excitation peak wavelengths may beused.

In some examples, a minimum proportion of spectral energy (e.g.,percentage of spectral energy) may be required for a desired excitationwavelength or within a desired excitation wavelength range. For example,if the excitation light source(s) 102 is a broad spectrum UV lightemitter, and the broad spectrum UV light emitter emits a total spectralenergy within a range of 300 nm to 400 nm, but the desired excitationwavelength range is 350 nm to 380 nm, a minimum proportion of spectralenergy in the range of 350 nm to 380 nm out of the total spectral energymay be configured to be a minimum percentage (e.g., 50%). In someexamples, the total spectral energy may be configured to be a minimumpercentage greater than 50%. In some examples, the total spectral energymay be configured to be a minimum percentage less than 50%. This minimumproportion of spectral energy may reduce energy usage towardsunnecessary wavelengths.

Irradiance, measured in milliWatts per centimeter squared (mW/cm²), maybe used to quantify how much excitation light from the excitation lightsource(s) may be required to initiate autofluorescence frommicroorganisms on a target surface. Irradiance may be adjusted byaltering the intensity (e.g., increasing the power) of the light comingout of the light source (e.g., brightness) and/or adjusting the distancebetween the excitation light source(s) and the target surface(s). Morepower may be required as the distance between the excitation lightsource(s) and the target surface(s) increases. In some examples, thecontamination sensing device 100 may provide a required minimumirradiance on the target surface(s). The required minimum irradiance maybe the minimum irradiance necessary to initiate autofluorescence. Therequired minimum irradiance may affect how this contamination sensingdevice 100 is designed into a room layout. As the distance between theexcitation light source(s) 102 and the target surface(s) increases, morepower may be used by the excitation light source(s) 102 to provide therequired minimum irradiance on the target surface(s).

In some examples, a minimum irradiance (e.g., 0.01 mW/cm²) at a surfacemay be required to initiate autofluorescence. Irradiance is the powerper unit area at a distance away from the light source. In someexamples, an irradiance of 0.05 mW/cm² may initiate autofluorescence ona surface, but higher values such as, for example, 0.1 mW/cm², 0.5mW/cm², 1 mW/cm², or 2 mW/cm² may be used. In some examples, higherirradiances may be required (e.g., 3 to 10 mW/cm²). In some examples, 10to 50 mW/cm² may be required. In some examples, greater than 50 mW/cm²may be required (e.g., 100 mW/cm²). In some examples, approximately1,500 mW/cm² may be required and/or utilized.

In some examples, lux (lumens/m²) may be used to quantify the excitationlight source(s) 102. In some examples, 500 lux may be required on thesurface. In some examples, a lux between 20,000,000 and 4,000,000,000may be used and/or required. In some examples, a radiant flux may berequired by the excitation light source of 50 to 250 Watts. Radiantflux, measured in Watts, is the total power from the light source.

In some examples, the irradiance on the target surface from theexcitation light source(s) 102 may be approximately 10 mW/cm², and theexcitation light source(s) 102 may be located 5 feet (152.4 cm) from thetarget surface. The excitation light source(s) 102 located 5 feet fromthe target surface with an irradiance of 10 mW/cm² may require a radiantflux out of the excitation light source(s) 102 of approximately 232.26Watts. In some examples, the excitation light source(s) 102 may belocated 1 foot (30.48 cm) from the target surface and may besubstantially directly above the target surface. The same irradiance of10 mW/cm² may be used on the target surface. The excitation lightsource(s) 102 located 1 foot from the target surface with an irradianceof 10 mW/cm² may require a radiant flux out of the excitation lightsource(s) 102 of approximately 9.29 Watts. These calculations areapproximations based on the inverse square law, as shown in Equation 1below and assuming the excitation light source is a point source,wherein E is the irradiance, I is the radiant flux, and r is thedistance from the excitation light source to a target surface.

$\begin{matrix}{E \cong \frac{I}{r^{2}}} & {{Equation}1}\end{matrix}$

The contamination sensing device 100 may be configured to detectirradiance. An irradiance sensor may be useful for determining theamount of light and/or disinfecting energy that is being delivered to asurface. The irradiance may be measured directly, for example, if thecontamination sensing device is mounted to a surface to be measured. Insome examples, the irradiance may be measured indirectly from areflection off of the surface to be measured by the sensor(s) 104. Insome examples, the sensor(s) 104 may be radiometrically calibrated usinga reference light source with a known emission spectrum and irradiance.New measurements may be compared to the stored calibration value todetermine irradiance or lux of a light being measured.

As described above, autofluorescence of contamination such as bacteriais the natural fluorescence emitted from bacteria after illuminatingsuch bacteria with a specific wavelength of light. Different bacteriamay be excited by different wavelengths of light and may emit differentwavelengths during autofluorescence. After being exposed to theexcitation light, light emitted from the bacteria may range, forexample, from 400 nm to 800 nm. Tryptophan is a compound that may befound in several different types of bacteria. Tryptophan emission maypeak at around 340 nm with dual excitation wavelengths of about 230 nmand 280 nm. Pyoverdine, for example, may be found in Pseudomonasstrains, and may have an emission peak, between 430 nm and 530 nm (e.g.,in the visible range), of about 455 nm, and a maximum excitationwavelength of about 395 nm. In some examples, a minimum quantity ofbacteria may be necessary to detect a measurable signal.

Many types of microorganisms/bacteria may fluoresce after exposure to anexcitation wavelength. For example, bacterial fluorescence may be due tobacteria containing intracellular and/or extracellular fluorophores.Bacteria of interest, for example, may include potentially pathogenicbacteria of concern to the healthcare industry as well as bacteriaassociated with contamination in the food processing industry.

Examples of detectable bacteria may include, for example, Pseudomonasaeruginosa, Escherichia coli, Salmonella, Campylobacter, Staphylococcusaureus, Staphylococcus carnosus, Clostridium difficile, Klebsiellapneumoniae, Serratia marcescens, Proteus mirabilis, as well as manyother gram positive and gram negative bacteria. Other bacteria that mayautofluoresce include, for example: Staphylococcus aureus (incl. MRSA),Clostridium perfringens, Clostridium difficile, Enterococcus faecalis,Staphylococcus epidermidis, Staphylococcus hyicus, Streptococcuspyogenes, Listeria monocytogenes, Bacillus cereus, Mycobacterium terrae,Lactococcus lactis, Lactobacillus plantarum, Bacillus circulans andStreptococcus thermophiles, Acinetobacter baumannii, Pseudomonasaeruginosa, Klebsiella pneumoniae, Proteus vulgaris, Escherichia coli,Salmonella enteritidis, Shigella sonnei, Serratia spp., and Salmonellatyphimurium. Some bacterial endospores may include Bacillus cereus andClostridium difficile. Other bacteria may also autofluorescence and bedetectable.

Non-living and/or non-organic surfaces may autofluoresce. In someexamples, the contamination sensing device 100 may be able to accountfor the emission of fluorescing light from a non-living and/ornon-organic surface (e.g., light that is not coming frommicroorganisms). Some common materials in healthcare settings mayinclude, for example, stainless steel, polypropylene, nylon polyesterpaint, microfiber cloth, bedding materials, plastics for nurse callsystems/buttons, etc. Other common surface materials include wood,paint, protective coatings, stone, metals, plastics, glass, concrete,paper composites, laminate, etc. In some examples, it may be determinedwhether cleaning residue remains on a surface to ensure such cleaningresidue does not interfere with surface bacterial load detection. Forexample, several common hospital materials including, for example,microfiber cloth, colored plastics (e.g., white, black, yellow, orange),stainless steel, polypropylene and several others, may fluoresce afterbeing exposed to excitation light. For example, microfiber cloth mayemit a peak wavelength in the range of 300-350 nm with excitationwavelengths of 280-340 nm. The microfiber cloth fluorescence may overlapwith some known bacterial emissions. In some examples, data, includingfluorescent profiles of common materials and cleaners, may be stored foruse in algorithms for determining surface bacterial load with thesematerials taken into consideration. Another common material inhealthcare and food processing settings is stainless steel, which mayfluoresce, for example, around 400-500 nm with excitation wavelengthsbetween 350-450 nm.

In addition to surfaces such as counters, fluorescence measurements ofsurfaces of various objects (e.g., computer keyboard, cell phone,bedding, food products, plants, medicines, etc.) may be taken. In someexamples where excitation light exposure is not harmful to humans, thefluorescence of a human may be measured. In some examples, fluorescencemeasurements may be obtained on a product level scale or an entire roomscale. Fluorescence may be measured for small surface areas (e.g., 1cm²) and/or large surface areas (e.g., 10 m²). Fluorescence may bemeasured for even smaller and larger surface areas. The location of thecontamination sensing device and the components of the contaminationsensing device may be adjusted appropriately for different applications.

In some examples, the contamination sensing device 100 may be handheld.A handheld contamination sensing device 100 may, for example, comprise asafety mechanism configured to determine a maximum irradiance exposurelimit. The contamination sensing device 100 may, based on the maximumirradiance exposure limit, determine a maximum irradiance emitted by theexcitation light source(s) 102. In some example, contamination sensingdevice 100 may determine if the sensor(s) 104 are directed normal to thesurface to be measured. The contamination sensing device 100 may, basedon readings from the sensor(s) 104, determine if the sensor(s) 104 aredirected normal to the surface to be measured. In some examples, thecontamination sensing device 100 may use computer vision algorithms todetermine if the sensor(s) 104 are directed normal to the surface to bemeasured.

In some examples, the contamination sensing device 100 or the individualcomponents of the contamination sensing device 100 (e.g., sensor(s) 104,excitation light source(s) 102, etc.) may be adjustable in height and/orlocation in order to accurately measure bacterial load on a desiredsurface. FIG. 2 shows an example contamination sensing device 100attached to an adjustable arm 206 at a distance ‘X’ 208 from a targetsurface 210. The adjustable arm 206 may enable movement of thecontamination sensing device 100. The adjustable arm 206 may be movable,for example, to increase or decrease the distance 208 from a targetsurface 210. The excitation light 212 from the excitation lightsource(s) 102 may be emitted towards the target surface 210.Microorganisms on the target surface 210 and/or the target surface 210may autofluoresce in response to the excitation light 212. Emitted light214 (e.g., light caused by autofluorescence) from the target surface 210(e.g., emitted by the surface and/or microorganisms on the surface) maybe detected by the sensor(s) 104. In some examples, the emitted light214 may comprise autofluorescence from microorganisms on the targetsurface.

An example ceiling mounted contamination sensing device 100 is shown inFIG. 3 . The contamination sensing device 100, or a component of thecontamination sensing device 100 (e.g., sensor(s) 104), may be mountedto allow for movement along the X, Y, and Z axes in the space, as wellas any degree of rotation. In some examples, the contamination sensingdevice 100 may be wireless, transportable, and/or easy to set up overany desired surfaces. In some examples, the contamination sensing device100 may be installed permanently in place in a room at an effectivelocation for measuring surface bacterial load. In some examples, thecontamination sensing device 100 may be part of a track system 302. Thetrack system 302 may be mounted, for example, on/near a ceiling 300 andmay allow for the contamination sensing device 100 to be easily moved.In some examples, an optional light fixture(s) 304 may be used to outputlight 306. The light 306 from the optional light fixture(s) 304 maycomprise illuminating light, excitation light to initiateautofluorescence, and/or disinfecting light. FIG. 3 illustrates thetrack system 302 configured in a grid pattern for the movement of itemsattached to the grid (e.g., contamination sensing device 100), but othertrack/rail patterns are possible. Additional sensor(s) 104 (e.g.,occupancy sensors) may be attached to the track system 302. In someexamples, the contamination sensing device 100 may be attached to amoveable arm capable of adjusting the location of the contaminationsensing device 100. In some examples, the movable arm 206 shown in FIG.2 may be attached/mounted to the track system 302 of FIG. 3 .

The contamination sensing device 100 (e.g., the excitation lightsource(s) 102 and/or sensor(s) 104) may be located at various heightsrelative to the target surface 210. In some examples, the target surface210 may be 1 to 4 feet from the floor, and the contamination sensingdevice 100 may be located on the ceiling 300, which may be 7 to 10 feetfrom the floor. In some examples, the contamination sensing device 100may be located anywhere from 1 inch to 10 feet from the target surface210. In some examples, the contamination sensing device 100 may belocated closer than 1 inch or further than 10 feet from the targetsurface 210. As the distance between the target surface 210 and thecontamination sensing device 100 increases, the intensity of theexcitation light 212 may be increased to provide an optimal irradianceon the target surface 210 to initiate the autofluorescence of bacteria.In some examples, the contamination sensing device 100 may be attachedto a mechanism (e.g., adjustable arm 206) making the distance betweenthe contamination sensing device 100 and the target surface 210adjustable in order to optimize the measurements. A motor, for example,may be incorporated into the track system 302 or the contaminationsensing device 100 so that the contamination sensing device 100 may moveon the track system 302 and/or to otherwise adjust its distance 208 tothe target surface 210. In some examples, the contamination sensingdevice 100 may be moved, for example, by a control system, which mayincrease or decrease the distance 208 between the target surface 210 andthe autofluorescence bacterial load sending device 100. As the distance208 between the target surface 210 and the contamination sensing device100 decreases, the surface area of the target surface 210 that may beobtained in the measurement also decreases.

In some examples, the contamination sensing device 100 may comprise adistance sensor. The distance sensor, for example, may be able to detectthe distance 208 from the contamination sensing device 100 to the targetsurface 210. The distance sensor, in some examples, may be aTime-of-Flight (ToF) based sensor, such as a laser distance finder orultrasonic ranger. In some examples, the autofluorescence load sensingdevice 100 may move (e.g., move to adjust the distance to the surface210) based on the distance 208. The distance sensor, in some examples,may be moveable to determine distance from different surfaces in aspace. In some examples where the contamination sensing device 100 ismounted permanently in place, the location of the contamination sensingdevice 100 may be calibrated prior to operation. The calibration maycomprise, for example, the distance between the contamination sensingdevice 100 and the target surface(s) 210.

In some examples, the surface area that may be measured by thecontamination sensing device 100 may depend on the emission angle of theexcitation light 212 and the distance 208 between the contaminationsensing device 100 and the target surface 210. In some examples, wherean excitation light source 102 comprises LED(s), the emission angle ofthe excitation light 212 may be 180 degrees or less (e.g., 130 degrees).In some examples, the surface area of the target surface 210 measured bythe contamination sensing device 100 may depend on a 3D distribution ofthe excitation light 212 and the distance 208 between the contaminationsensing device 100 and the target surface 210. In some examples, thedistribution of the excitation light 212 may be cosine or Gaussian. Insome examples, the surface area of the target surface 210 that may bemeasured by the contamination sensing device 100 may depend on a fieldof view of the camera/sensor(s) 104 of the contamination sensing device100 and the distance 208 between the contamination sensing device 100and the target surface 210. In some examples, the field of view of acamera may be 360 degrees. Spherical cameras, for example, may be ableto capture a 360 degree image. In some examples, the field of view of acamera may be less than 360 degrees. The sensor(s) 104 may be capable ofmoving to cover a greater surface area (e.g., panoramic imaging). Forexample, the sensor(s) 104 may be capable of moving via the adjustablearm 206 and/or the track system 302. In some examples where thesensor(s) 104 is a photodiode or an array of photodiodes, the surfacearea of the target surface 210 that may be measured by the contaminationsensing device 100 may depend on the field of view of the photodiode(s)and/or the distance 208 between the contamination sensing device 100 andthe target surface 210. Photodiodes may be less sensitive to detectingwavelengths as the angle of the emitted light 214 changes from a linedirectly into the photodiode. The field of view may be measured by anangle of half sensitivity (e.g., the angle at which the photodiodedetects half of the emitted light 214). In some examples, a photodiodemay have a narrow field of view (e.g., an angle of half sensitivity of15-20 degrees). In some examples, a photodiode may have a wide field ofview (e.g., an angle of half sensitivity of 50-65 degrees).

In some examples, the contamination sensing device 100 may determinecoordinates of a bacterial load on the target surface 210 (e.g., (x,y)coordinates). The contamination sensing device 100 may set a (0,0)coordinate point (e.g., virtual coordinate point) on the target surface210 and use the coordinate point to determine relative location(s) ofsurface bacterial load. The contamination sensing device 100 maydetermine a multitude of (x,y) coordinate points to map the location ofbacterial load. In some examples, the contamination sensing device 100may determine various representative functions (e.g., lines or circles)to map the location of bacterial load. In some examples, the bacterialload coordinates or representative function information may be used in aprocess of creating a contamination map. In some examples, thecontamination map (and associated bacterial load coordinates orrepresentative function information) may be used with a disinfectinglighting system, as shown in FIG. 12 (e.g., disinfecting lighting system1200), to direct, via a control system/controller or processor,disinfecting light to increase/decrease/locate areas of contamination.In some examples, the contamination sensing device 100 may incorporate alaser. In some examples, an algorithm may calculate a centroid of thebacterial load by locating high areas of bacterial load that measureabove a threshold value. In some examples, the threshold value maycomprise a predetermined threshold value. In some examples, thethreshold value may be calculated by the contamination sensing device100. In some examples, the threshold value may be determined based onhistorical bacterial load data. Based on the location of the calculatedcentroid of the bacterial load, the contamination sensing device 100 maydirect the laser to point at the location of the centroid. Thecontamination sensing device 100 may direct the laser to step/movethrough the target surface 210 area from highest level of bacterial loadto lowest level of bacterial load above the threshold value. The lasermay be used as an inspection and/or training tool. The laser may be usedto indicate high risk surface areas for targeted cleaning (e.g., used bystaff to target cleaning to high risk surface areas).

In some examples, the contamination sensing device 100 may use a seriesof excitation light source(s) 102 with different output wavelengths forexcitation. The contamination sensing device 100 may use a series ofsensor(s) 104 with different wavelength filters to detect fluorescenceemissions. The use of different series of excitation light source(s) 102and sensor(s) 104 may allow different types of microorganisms/bacteriato be characterized by determining which excitation spectra the bacteriarespond to.

FIGS. 4A-6B illustrate various example configurations of excitationlight source(s) 102, sensor(s) 104, control systems, and objects. Insome examples, a physical enclosure may house the contamination sensingdevice 100 and/or components (e.g., light source(s) 102, sensor(s) 104)of the contamination sensing device 100. In some examples, the volume ofthe physical enclosure may be 4000 cm³. In some examples, the volume ofthe physical enclosure may be less than or greater than 4000 cm³.Objects may be put within a small enclosure (e.g. a cell phone) andmeasurements may be taken on the object within the enclosure.

FIG. 4A shows a side/cross-sectional view of an example enclosure 400integrated with a contamination sensing device 100 comprising theexcitation light source(s) 102 and sensor(s) 104. The sensor(s) 104 ofthe autofluorescence bacterial load sending device 100, as shown in FIG.4A, may, for example, comprise a camera sensor 402. The autofluorescencebacterial load sensing device 100 may comprise excitation lightsource(s) 102 mounted remote from the camera sensor 402. The excitationlight source(s) 102 may be mounted, for example in the corners of theenclosure 400, at the edges of the enclosure, on the ceiling of theenclosure 400, and/or on the walls of the enclosure 400. Theautofluorescence bacterial load sending device 100, as shown in FIG. 4A,may comprise two excitation light source(s) 102. In some examples, morethan two excitation light source(s) 102 may be used. An object 404comprising the target surface 210 may be located inside the enclosure400. In some examples, the enclosure 400 may comprise a room with a door406. The excitation light source(s) 102 may emit excitation light 212towards an object 404 comprising the target surface 210. Emitted light214 (e.g., emitted fluorescence) from the target surface 210 may becaptured by the camera sensor 402. FIG. 4B shows a top view of theexample enclosure 400 integrated with the contamination sensing device100 of FIG. 4A.

FIG. 5A shows a side/cross-sectional view of an example enclosure 500integrated with a contamination sensing device 100. The sensor(s) 104 ofthe autofluorescence bacterial load sending device 100, as shown in FIG.5A, may be a photodiode based sensor comprising, for example, an 8×8photodiode array 502. An object 504 comprising the target surface 210may be located inside the example enclosure 500. In some examples, theenclosure 500 may comprise a room with a door 506. The excitation lightsource(s) 102 may emit excitation light 212 towards the target surface210. In some examples, as shown in FIG. 5A, the excitation lightsource(s) 102 may be mounted to and/or located on a wall 510. Emittedlight 214 (e.g., emitted fluorescence) may be captured by the photodiodearray 502 and from the target surface 210. FIG. 5B shows a top view ofthe example enclosure 500 integrated with the contamination sensingdevice 100 of FIG. 5A.

FIG. 6A shows a side view of an example enclosure 600 integrated with acontamination sensing device 100. The light source(s) 102 of theautofluorescence bacterial sensing device 100 may, for example, bemounted to and/or located on/near a wall 510. The enclosure 600 maycomprise an array of lighting element(s) 601 (e.g., LEDs) able to emitdisinfecting light (e.g., light within a range of 380-420 nm).Disinfecting light may, for example, comprise a wavelength in a range of380 to 420 nm, e.g., 405 nm, and may reduce the presence ofcontamination such as bacteria. The 380 to 420 nm wavelengths of lightmay inactivate microorganisms such as but not limited to: Escherichiacoli (E. coli), Salmonella, Methicillin-resistant Staphylococcus aureus(MRSA), Clostridium difficile, and a wide variety of yeasts and/orfungi. In some examples, disinfecting light includes light with adisinfecting dosage sufficient to stop, decrease, impede, or eliminatebacteria and/or bacteria population growth. In some examples, thedisinfecting dosage may be characterized in terms of irradiance or withunits such as, for example, milliwatts per centimeter squared (mW/cm²).In some examples, the disinfecting dosage may have a minimum irradiancethreshold at or around 0.01 mW/cm². In some examples, the disinfectingdosage may be characterized in terms of radiant exposure with units suchas, for example, Joules per centimeter squared (J/cm²).

In some examples, disinfecting light may have an irradiance of at least0.01 or 0.02 mW/cm², e.g., from lighting element(s) 601. Disinfectinglight may have any color desired, so long as sufficient light todisinfect in the 380 to 420 nm range is present therein. Disinfectinglight may be solely between 380 to 420 nm wavelength light. In someexamples, disinfecting light may include or be converted to include atleast one additional portion of light above 420 nm to createdisinfecting light of another color, such as white light.

The lighting element(s) 601 able to emit disinfecting light may, forexample, be mounted/attached to the ceiling 608 of the enclosure 600.The enclosure 600 may comprise a photodiode array 602 as part of thecontamination sensing device 100. The photodiode array may, for example,be mounted/attached to the ceiling 608 of the enclosure 600. An object604 comprising the target surface 210 may be located inside theenclosure 600. In some examples, the enclosure 600 may comprise a door606. The light source(s) 102 may emit excitation light 212 towards thetarget surface 210. Emitted light 214 (e.g., emitted fluorescence) fromthe target surface 210 may be captured by the photodiode array 602. Thecontamination sensing device may use the excitation light 212 todetermine bacterial load. The lighting element(s) 601 may, based on thebacterial load, emit disinfecting light to inactivatebacteria/microorganisms. In some examples, the lighting element(s) 601may emit disinfecting light based on the bacterial load exceeding athreshold bacterial load. FIG. 6B shows a top view of the exampleenclosure 600 integrated with the contamination sensing device 100 ofFIG. 6A.

The enclosures 400, 500, 600 may be openable or closeable via, e.g.,hinged or sliding doors 406, 506, 606. In some examples, the enclosures400, 500, 600 may be approximately opaque to keep the excitation light212 within the enclosure 400, 500, 600. The enclosures 400, 500, 600 maycomprise a control system (e.g., controller) 610 for controlling thecontamination sensing device 100 and/or the lighting elements 601 ableto emit disinfecting light. The enclosures 400, 500, 600 may be of anydimension. In some examples, the enclosures 400, 500, 600 may berelatively small (e.g., 12 inches by 12 inches or smaller) and be ableto contain individual items. In some examples, the enclosures 400, 500,600, may be large (e.g., an entire room). In some examples, theexcitation light source(s) 102 may be mounted at a 90 degree angle fromthe sensor(s) 104 as shown in FIGS. 5A-6B. In some examples, thesensor(s) 104 may be mounted at the top of the enclosure andsubstantially or directly above the target surface 210 as shown in FIGS.4A-6B.

The contamination sensing device 100 may be integrated directly intoanother device or appliance (e.g., an add-on in a disinfecting lightingfixture or inside a refrigerator). The contamination sensing device 100,for example, may be powered through line power, through anotherdevice/appliance's low voltage power, power outlets, electrical powersupplies, batteries or rechargeable batteries mounted in proximity tothe appliance, and/or though wireless or inductive charging. Whererechargeable batteries are employed, they may be recharged, for example,using alternating current power and/or solar panels (not shown).

In some examples, as shown in FIG. 7 , the contamination sensing device100 may be integrated into a disinfecting light fixture 700. Thedisinfecting light fixture 700, for example, may be an overhead lightingfixture or task light. The disinfecting light fixture may emitdisinfecting light which may, for example, comprise a wavelength in arange of 380 to 420 nm, e.g., 405 nm, and may reduce the presence ofcontamination such as bacteria. The disinfecting light fixture 700 andbacterial load sensing device 100 may be in communication with eachother through a control system 610 (e.g., controller) to allow for thedata from the sensor(s) 104 to be used in the decision making processfor controlling the output of the disinfecting light fixture 700. Insome examples, the control system 610 may adjust the output of thedisinfecting light based on data from the sensor(s) 104. In someexamples, the control system 610 may adjust the irradiance of thedisinfecting light emitted by the disinfecting light fixture, forexample, based on the data from the sensor(s) 104. In some examples, thecontrol system 610, based on the data from the sensor(s) 104 of thecontamination sensing device 100, may adjust the amount of time thedisinfecting light fixture 700 emits the disinfecting light. FIG. 7provides an example where the contamination sensing device 100 isphysically coupled to a disinfecting lighting fixture 700 (e.g., atroffer fixture). In some examples, the contamination sensing device 100may not need to be physically coupled to a disinfecting light fixture700 and/or system to be in communication with the disinfecting lightfixture 700 and/or system. In some examples, the contamination sensingdevice 100 may be separate from the disinfecting light fixture 700and/or system. In some examples, the contamination sensing device 100may be in wireless communication with the disinfecting light fixture,for example, through the control system 610.

A flowchart showing an example process 800 for taking a measurementusing a contamination sensing device 100 is illustrated in FIG. 8 . Thecontrol system 610 of the contamination sensing device 100 may receivean instruction to take a measurement of the environment at step 802. Insome examples, the environment may be preferred to be dark or otherwisenot fully illuminated for the contamination sensing device 100 to workmost effectively. In some examples, the sensor(s) 104 may capture anoptional dark image. A dark image may be obtained, for example, bytaking an image with the excitation light source(s) 102 turned off. Thecontamination sensing device 100 may determine, using the sensor(s) 104,if the ambient light in the environment is low enough to take ameasurement at step 804 (e.g., determine if the amount of ambient lightis below a light threshold). If the ambient light in the environment islow enough to take a measurement (step 804: YES), the contaminationsensing device 100 may take a measurement at step 806. If the ambientlight in the environment is not low enough to take a measurement (step804: NO), the control system 610 may turn off all lights in theenvironment (e.g., excitation light source(s) 102, ambient lighting,etc.) at step 808. The contamination sensing device 100 may then take ameasurement, with the lights off, at step 806.

The control system 610 may turn on the excitation light source(s) 102 atstep 808. The excitation light source(s) 102 may flash the excitationlight 212 at high power for a short amount of time (e.g., 1 microsecondto 3 seconds) to initiate autofluorescence. During emission of theexcitation wavelength, the sensor(s) 104 may capture the fluorescenceimage data at step 810. The excitation light source(s) 102 may turn offafter the sensor(s) 104 captures the fluorescence image data at step812. In some examples, the excitation light source(s) 102 may turn offbefore the sensor(s) 104 captures the fluorescence image data. Thecontrol system 610 may determine if a new picture of the environment isneeded at step 814. A new picture of the environment may be needed, forexample, if the surface/environment has changed. If a new picture of theenvironment is not needed (step 814: NO), the bacterial load sensorreading is complete at step 816. If a new picture of the environment isneeded (step 814: YES), the control system 610 may turn on ambientlighting in the environment at step 818. The control system 610 may takea picture of the environment at step 820. In some examples, the controlsystem 610 may take a picture to determine if the surface/environmenthas changed. If the surface/environment has changed, the control system610 may save the new picture of the environment, for example, to createa composite image. The sensor(s) 104 and/or a secondary/additionalsensor (e.g., a camera) may capture the image of the space using whitelight illumination of the space or by optionally using a flash ofvisible or infrared (IR) light to illuminate the space. After taking thepicture of the environment, the bacterial load sensor reading may becomplete at step 816.

Using the data collected by the sensor(s) 104, the contamination sensingdevice 100 may create an image(s) showing contamination (e.g., bacteria)hotspots, referred to in this disclosure as a contamination map. In someexamples, the contamination map may comprise a picture of the spacetaken by a regular camera as an overlay. In some examples, an additionalregular color (visible light), grayscale, or infrared (IR) camera may beused in conjunction with the sensor(s) 104 to generate a room/enclosureimage. The room/enclosure image may be overlaid with the contaminationmap to create a composite image, similar in appearance to imagesproduced by high-end thermal cameras, similar to, for example, a heatmap or a contour map. FIG. 9 shows an example contamination map 900image with a key 902 to read the levels of bacterial load 904 orconcentration of bacterial load 904 on a surface 906. Bacterial load 904may be indicated by certain colors within the contamination map 900 anddefined by the key 902.

Changes in surface bacterial load detected by the contamination sensingdevice 100 may be determined through a variety of methods. Thecontamination map 900 indicating the location and quantity of bacteriamay be provided by the contamination sensing device 100. Thecontamination map 900 of microorganism/bacteria may show the locationsof microorganisms/bacteria on a surface and use colors with a key 902,for example, to denote the density/concentration of bacteria in thoselocations. The key 902 may include a correlated number scale, a ‘low’ to‘high’ scale, or more specific measurements of bacteria concentrations.

FIG. 10 shows an example flowchart of an example process 1000 for makinga sensor image and/or contamination map 900 from the sensor data. Thecontamination sensing device 100 may perform computer vision processing,for example, to filter out noise, highlight microorganisms in the image,or count and locate microorganisms. Once a dark image, fluorescenceimage, and/or room image are taken, computer vision algorithms may beused to create a final image (e.g., contamination map 900). Thefollowing is an example procedure to arrive at the final image. Thecontamination sensing device 100 may obtain a microorganism/bacterialload sensor reading (e.g., fluorescence image data) from the sensor(s)104 and the data may be ready for processing at step 1002. In someexamples, dark image data 1004 from the dark image may be subtractedfrom fluorescence image data 1006 from the fluorescence image at step1008, for example, to reduce noise from ambient light or the sensor(s)104. In some examples, a color filter and/or mask may be used to isolatecolors above a certain threshold at step 1010. In some examples, an edgedetection algorithm may be used to further isolate concentrations ofcolors at step 1010. The computer may save this processed image for usein determining bacterial load (e.g., performing bioburden analysis) atstep 1012. In some examples, the remaining steps may make the imageeasier to interpret. In some examples, false coloring may be added forimage clarity by mapping different intensities of a single color or agreyscale range to a range of colors at step 1014. The addition of falsecoloring may, for example, be useful for photodiode sensor(s) which mayonly output intensity values per sensor, instead of a colored pixel. Insome examples, an algorithm may create a composite image by processingfluorescence image data 1006 and the room image together at step 1016Creation of the composite image may be performed, for example, byaddition or weighted blending with transparencies. The sensor image maybe complete at step 1018.

The contamination sensing device 100 may be standalone, or part of amesh network of devices (e.g., connected to other sensor(s) 104, lights,and controls). The contamination sensing device 100 may connect, over alocal intranet or over the internet, to a server and sendinstructions/data (e.g., raw or processed data) to the server and/orreceive instructions/data from the server. The server may comprise oneor more servers, may be connected to several devices, and/or may relaycommands between these servers and/or devices. When both thecontamination sensing device 100 and a lighting system are connected tothe same network (e.g., mesh network or server network), thecontamination sensing device 100 may send instructions, such as, forexample, to turn the lighting system off (e.g., to reduce the amount ofambient light in the space) while taking a bacterial load reading.

FIG. 11 illustrates an example contamination sensing device 100 incommunication with a processor 1100 (e.g., processor capable of computervision algorithms) and a user interface 1102 (e.g., interface to displaydata). The contamination sensing device 100 may make use of processors1100 such as, for example, central processing units (CPU), applicationspecific processors (APU), graphics processing units (GPU), or digitalsignal processor (DSP) to process data. The contamination sensing device100 may have wireless antennas and/or chips for Bluetooth (BLE), Wi-Fi,long or short-range radio, and/or cellular connections. Components ofthe contamination sensing device 100 (e.g., excitation light source(s)102, sensor(s) 104, control system 602, etc.) may be electricallyconnected and/or may be wirelessly connected via the wireless antennasand/or chips. The contamination sensing device 100 may have memoryand/or storage for holding instructions/data. The contamination sensingdevice 100 may contain a System on a Chip (SoC) that may incorporatesome or all of the aforementioned functionality.

FIG. 12 shows a contamination sensing device 100 in communication with acontrol system 610 and a disinfecting lighting system 1200. Thecontamination sensing device 1200 may be in communication with theprocessor 1100. The processor 1100 may provide communication with theuser interface 1102, control system 610, and/or disinfecting lightingsystem 1200. As further described herein, the functions of processor1100 of FIG. 11 or 12 or the control system 610 of FIG. 12 may beimplemented by the processor 2201 of example computing device 2200 ofFIG. 22 .

A contamination map/composite image, such as, for example, a compositeimage created using the process shown in FIG. 10 , may show high riskareas in a real space and may allow for deployment of cleaning personnelto those specific areas. The composite image may be processed bycomputer vision algorithms, allowing a computer to decide where the highrisk areas may be in a space. The processed data may, for example, beused by a disinfecting lighting system 1200. The disinfecting lightingsystem 1200 may emit disinfecting light. Disinfecting light may, forexample, comprise a wavelength in a range of 380 to 420 nm, e.g., 405nm, and may reduce the presence of contamination such as bacteria. Usingthe processed data, the disinfecting lighting system 1200 may increasethe dosage in the effected room, space, or zone, with the intention ofreducing the bacterial load in the high risk area(s). In some examples,the control system 610 may determine, based on the processed data, thata surface is contaminated (e.g., the bacterial load exceeds a bacterialload threshold). In some examples, the control system 610 may, based onthe contamination of the surface, send instructions to the disinfectinglighting system 1200 to emit the disinfecting light. In some examples,the control system 610 may determine, based on the level ofcontamination sensed by the contamination sensing device 100, the dosageof disinfecting light. The disinfecting lighting system 1200 may, forexample, adjust wavelengths of disinfecting light emitted, irradiance ofthe disinfecting light, the amount of time the disinfecting lightingsystem 1200 emits the disinfecting light, etc., based on theinstructions from the control system 610. The processed data from thecontamination sensing device, may indicate the location of contaminationon a surface. The disinfecting lighting system 1200, may adjust thedisinfecting light based on the location of the contamination. Forexample, the disinfecting lighting system 1200, may increase the dosageof disinfecting light for an area indicated as containing contaminationby the contamination sensing device 100. Use of the processed data, forexample, by the disinfecting lighting system 1200, may allow forautomated reduction of bacterial load with minimal to no humanintervention.

In some examples, the sensor(s) 104 may be a single photodiode, an arrayof photodiodes, an array of Single Photon Avalanche Diodes (SPAD),and/or an optical phased array, with or without bandpass filters. FIG.13 shows a front view of an array 1300 of photodiodes 1302. The array1300 of photodiodes 1302 may be arranged in a grid pattern (e.g., 8×8,32×32, 128×64, etc.). Each diode 1302 may be treated as a pixel and thegrid may represent the total number of pixels in the generated image.Each pixel may contain an intensity value representing the amount offluorescence detected. While most configurations may have far fewerpixels (e.g., 256 pixels compared to hundreds of thousands or more for atypical camera), each diode 1302 may be more sensitive than a typicalcamera pixel. Increased sensitivity may allow for better detection ofdifferent levels of intensity emitted from the bacteria.

A 1D array 1400 (e.g., a line of sensor(s) 104, linear array ofsensor(s) 104) may be used alternatively or in addition to a 2D array orgrid of sensor(s) 104. FIG. 14 shows a front view of a 1D array 1400 ofphotodiodes 1302. A 1D array 1400 may allow the contamination sensingdevice 100 to scan along one axis. To measure along a second axis, the1D array 1400 of sensor(s) 104 (e.g., photodiodes 1302 and/ormultispectral sensors) may be coupled to a motor and/or servo, which maythen be able to move/rotate the 1D array 1400 of sensor(s) 104 to takemeasurements along the second axis. In some examples, the 1D array 1400of sensor(s) 104 may be coupled to an adjustable arm 206 and/or tracksystem 302 to enable movement of the 1D array 1400 of sensor(s) 104.Each of the sensor(s) 104 in an array 1400 may, for example, beconfigured to detect a different wavelength. In some examples, thesensor(s) 104 in an array 1400 may comprise filters. In, some examples,the filters may be mounted to the sensor(s) 104 or otherwise disposed inthe path of light entering the sensor(s) 104. In some example, eachfilter associated with each different sensor(s) 1400 in an array 1400may block/reduce different wavelengths of light. In some examples, anarray 1400 may be a group of sensor(s) 104. In some examples, the groupof sensor(s) 104 may detect light having substantially the samewavelengths. In some examples, the group of sensor(s) 104 may detectlight having substantially different wavelengths. In some examples,groups of sensor(s) 104 may any assortment of sensor(s) configured todetect substantially the same or different wavelengths.

In some examples, the sensor(s) 104 may comprise an array ofmultispectral sensors or spectrometers. In some examples, amultispectral sensor may comprise a plurality of photodiodes. Eachphotodiode may comprise a filter configured to reduce/block wavelengthsof light. In some examples, each photodiode may comprise a differentfilter. Each different filter, for example, may reduce/block differentwavelengths of light. In some examples, the multispectral sensorcomprising a plurality of photodiodes and associated filters may measurewavelengths of light. In some examples, each photodiode may beconfigured to respond to a different wavelength or range of wavelengths.

FIG. 15 illustrates an image produced by example sensor arrays. Thesesensor arrays may be used to detect and measure fluorescence emissionspectra across a range of wavelengths, with measurements in intensityper wavelength. Compared to a photodiode array, which measures overallintensity in a wavelength range, multispectral sensors or spectrometersmay give a substantially higher resolution measurement ofautofluorescence response. Each pixel in the contamination map generatedby the multispectral sensors or spectrometers may consist of a spectralpower distribution (SPD), which contains intensity per wavelength ofeach wavelength measured.

FIG. 15 shows an example composition of fluorescence image 1500 from thesensor(s) 104. The sensor(s) 104 may be, for example, a camera sensor,photodiode sensor(s), and/or multispectral/spectrometer sensor(s). Thefluorescence image 1500 may comprise an array of pixels 1502. The numberof pixels 1502 in the array of pixels 1502 may vary, for example, basedon the resolution and/or number of sensor(s) 104. In some examples, eachpixel 1502 may correspond to one sensor 104. In some examples, eachpixel 1502 may correspond to multiple sensor(s) 104. In some examples,each pixel may represent data from a single sensor performing multiplemeasurements with different filters. In some examples, the resolutionmay be based on the resolution of a camera sensor. In some examples, theresolution may be based on the number of photodiode sensors and/ormultispectral/spectrometer sensors. The fluorescence image 1500 shown inFIG. 15 comprises an 8×8 array of pixels 1502. In some examples, thenumber of pixels could be much higher (e.g., 1024×1024 or higher). Eachpixel 1502 in the array of pixels 1502 may comprise a value indicating acolor intensity. Each pixel 1502 may have an intensity value. In someexamples, each pixel 1502 may have an intensity value for each color,such as, for example, when a camera is used. For example, each pixel1502 may comprise a separate color intensity value for each of red,green, and blue. In some examples, each pixel 1502 of the array ofpixels 1502 may comprise an SPD measured by themultispectral/spectrometer sensor(s). In some examples, each pixel maycorrespond to a plurality of wavelengths.

Ambient light may contribute to background noise that may be observed bythe sensor(s) 104. Background noise may be caused, for example, bylighting fixtures, natural sunlight (e.g., sunlight through a window),or other devices that generate light. In some examples, the excitationlight source(s) 102 may provide background noise if the excitation light212 is taken in by the sensor(s) 104. In some examples, the fluorescencesignal from microorganisms on the target surface 210 may have a lowirradiance. Background noise may be reduced to a lower irradiance thanthe fluorescence signal to detect the fluorescence signal. In someexamples, the fluorescence signal may become indistinguishable frombackground noise. In some examples, there may be a maximum threshold ofbackground lux or irradiance that the ambient light may optimally bebelow before a measurement is initiated. Bandpass and/or high-passfilters may be used on the sensor(s) 104 to filter out undesiredwavelengths such that only wavelengths of interest are observed by thesensor(s) 104. In some examples, excitation light 212 may enter thesensor(s). A dichroic filter or cosine corrector, may only allow lightto enter at certain angles, and may be used to keep stray excitationlight 212 from entering the sensor(s) 104.

In some examples, the sensor(s) 104 may be a camera with a bandpassfilter. FIG. 16A shows a sensor 104 comprising a camera 1600 with abandpass filter 1602. In some examples, the bandpass filter 1602 mayblock/reduce wavelengths except those known to be emitted by thefluorescence of the target microorganisms. The camera 1600 may then onlysee the fluorescence of the microorganisms in a 2D field. The intensityof the observed colors and/or wavelengths may be used to determinerelative quantity of bacteria and/or calibrated against a reference thatcorresponds to a known bacteria count (e.g., measured in CFU, todetermine actual approximate quantity). FIG. 16B shows a sensorcomprising an array of photodiodes 1302. The bandpass filter 1602 mayblock/reduce wavelengths except those known to be emitted by thefluorescence of the target microorganisms from reaching the photodiodes1302. FIG. 16C shows an array of photodiodes 1302 without the bandpassfilter 1602. In some examples, photodiodes 1302 may not have a bandpassfilter 1602. In some examples, a filter adjuster may move the bandpassfilter 1602 over the photodiodes as shown in FIG. 16B and adjustablyremove the bandpass filter 1602 from covering the photodiode sensors1302 as shown in FIG. 16C. The sensor(s) 104 (e.g., camera 1600,photodiodes 1302) may provide a detailed 2D contamination map ofbacterial load, where each pixel represents the color, wavelength,and/or intensity of fluorescence. The map may be false-colored withbacteria density levels, for example, similar in appearance to an imageone might get from a thermal camera.

In some examples, sensor(s) 104 may be produced or calibrated to respondto certain wavelengths of light, which may eliminate the need for afilter. In some examples, sensor(s) 104 may be calibrated to respond toa known wavelength that may autofluoresce from a targetbacteria/microorganism. Calibration may be performed, for example,during an initial setup of the contamination sensing device 100. In someexamples, calibration may be performed by the control system 602 beforetaking a measurement with the sensor(s) 104. In some examples, thecontrol system 602 may adjust and/or change the calibration of thesensor(s), for example, based on an excitation wavelength,autofluorescence wavelength,

In some examples, the sensor(s) 104 may be configured to receive lightin the visible spectrum. In some examples, the sensor(s) 104 may beconfigured to receive near-ultraviolet, ultraviolet (UV), near-infrared,or infrared (IR) wavelengths. The sensor(s) 104 may have a filter and/orcoating that blocks/reduces wavelengths not of interest and allows onlythe fluorescence of the microorganisms. In some examples, a plurality offilters may be used alone or in conjunction with each other.

In some examples, a filter and/or coating may be automatically ormanually adjustable and/or removable. In some examples, excitation lightmay be detectable by the sensor(s) 104. The filter or coating may beadjusted to block/reduce excitation that may enter the sensor(s) 104. Insome examples, the filter or coating may block/reduce all wavelengthsexcept for wavelengths that may be emitted through autofluorescence of atarget bacteria/microorganism. The contamination sensing device 100(e.g., the control system 610) may adjust the filter or coating todetermine the presence of a target bacteria. For example, thecontamination sensing device 100 may emit an excitation light having awavelength known to cause autofluorescence in a target bacteria towardsthe target surface 210. The sensor(s) 104 may comprise a filter orcoating that may be adjusted to filter/reduce the excitation light fromentering the sensor(s) 104. The filter or coating may, for example, beadjusted to block/reduce wavelengths that do not autofluoresce from thetarget bacteria, allowing wavelengths that fluoresce from the targetbacteria to be detected by the sensor(s) 104.

The contamination sensing device 100 may detect contamination bydetecting wavelengths of light that are known to be emitted bycontamination in response to excitation wavelengths of light. Thecontrol system 610 may adjust the wavelengths of light emitted by theexcitation light source to detect various types of contamination. Thecontrol system 610 may, for example, access a database to determineexcitation and/or emission spectra of different types of contamination.The control system 610, based on the excitation spectra, mayautomatically adjust the wavelengths of light emitted by the excitationlight source(s) 102. The control system 610 may, based on the excitationspectra and/or the emission spectra, automatically adjust the filterand/or coating to block reduce wavelengths of light. The control system610 may cycle through various excitation and emission spectra to detectcontamination.

In an example, the contamination sensing device 100 may emit anexcitation light having wavelengths of about 230 nm and 280 nm, whichare known to cause autofluorescence in tryptophan. The contaminationsensing device 100 may adjust a filter and/or coating to block/reducewavelengths of about 230 nm and 280 nm from the sensor(s) 104. Thecontamination sensing device 100 may adjust the filter or coating toblock/reduce wavelengths outside of approximately 340 nm, which may beemitted through autofluorescence of tryptophan. The filter or coating,for example, may allow the autofluorescence of tryptophan at 340 nm tobe detected by the sensor(s) 104. The contamination sensing device 100,based on the sensor(s) 104 detecting light of approximately 340 nm, maydetermine that a microorganism containing tryptophan is the targetsurface. The contamination sensing device 100 may adjust the filterand/or coating to block/reduce other wavelengths to detect contaminationthat does not contain tryptophan.

The contamination sensing device 100 may adjust the filter or coating,for example, with the control system 610. In some examples, the filtermay be a physical filter. In some examples, the filter may be mounted tothe sensor(s) 104. In some examples, the filter may be mounted in frontof the sensor(s) 104. In some examples, the sensor(s) 104 may comprisethe filter. In some examples, the filter may be a digital filter and maybe applied by the control system 610.

In some examples, the contamination sensing device 100 may comprisemultiple filters. The filters may, for example, comprise bandpassfilters, dual bandpass filters, multi bandpass filters, high-passfilters, and/or low-pass filters. In some examples with a plurality ofsensor(s) 104, each sensor(s) may comprise a filter. In some exampleswith a plurality of sensor(s) 104, each sensor(s) 104 may comprise adifferent filter configured to block/remove different wavelengths oflight. In some examples, the contamination sensing device 100 maycomprise a filter adjuster to dispose one or more filters in front ofthe sensor(s) 104. The filter adjuster may move a filter in front of thesensor(s) 104 to reduce/remove a wavelength (e.g., wavelength range) oflight. In some examples, the contamination sensing device 100 may usethe control system 610 to indicate, to the filter adjuster, which filterto use. The contamination sensing device 100 may change the filter usedby the contamination sensing device 100 to determine the presence of atarget bacteria. For example, the contamination sensing device 100 mayemit an excitation light having a wavelength known to causeautofluorescence in a target bacteria towards the target surface 210. Afilter may be used to filter/reduce the excitation light from enteringthe sensor(s) 104. The filter, in some examples, may be selected toblock/reduce wavelengths that do not autofluoresce from the targetbacteria, allowing wavelengths that autofluoresce from the targetbacteria to be detected by the sensor(s) 104.

In some examples, the filter adjuster may comprise a plurality offilters on a wheel/disk. The filter adjuster may rotate the wheel/diskto move one of the plurality of filters in front of the sensor(s) 104.The filter adjuster may rotate, for example, using a motor orservomechanism. The control system 610 may rotate the wheel/disk to movethe desired filter in front of the sensor(s) 104. The wheel/disk maycomprise any number of filters. In some examples, the filter adjustermay comprise one or more filters on a hinge. The filter adjuster may,for example, move one or more of the hinged filters in front of thesensor(s) 104. In some examples, the filter mechanism may linearly moveone or more filters into and/or out of the path of light directed towardthe sensor(s) 104. In some examples, a first filter may be mounted overthe sensor(s) 104 and the filter adjuster may be configured to move asecond filter in front the sensor such that light directed toward thesensor passes through both the first filter and the second filter. Insome examples, the first filter may be a high pass filter that filtersexcitation wavelength below, for example, 405 nm, and the second filtermay be a lowpass filter that, in combined use with the first filter,results in a bandpass filter.

To detect contamination, the contamination sensing device 100 may emitwavelengths of light known to excite bacteria. For example, thecontamination sensing device 100 may emit an excitation light havingwavelengths of about 230 nm and 280 nm, which are known to causeautofluorescence in tryptophan. The contamination sensing device 100 mayadjust a filter to block/reduce wavelengths of about 230 nm and 280 nmfrom the sensor(s) 104. The filters may be adjusted by a filteradjusting moving one or more filters in front of the sensor(s) 104. Thecontamination sensing device 100 may select a filter to block/reducewavelengths outside of approximately 340 nm, which may be emittedthrough autofluorescence of tryptophan. The filter, for example, may bea bandpass filter with a 50 nm band, and may, for example, block/reducewavelengths outside of 315-365 nm. The filter, for example, may allowthe autofluorescence of tryptophan at 340 nm to be detected by thesensor(s) 104. The contamination sensing device 100, based on thesensor(s) 104 detecting light of approximately 340 nm, may determinethat a microorganism containing tryptophan is the target surface. Insome examples, the contamination sensing device 100 may use filters toblock/reduce other wavelengths to detect contamination thatautofluoresces at different wavelengths than tryptophan.

Example bandpass filters 1602 that may be utilized by the sensor(s) 104may include dual-bandpass filters such as, for example: Edmund Optics#87-242 or Chroma 59009m, dual band FL filter (e.g., λ_(emiss)=500-550nm and 590-690 nm). In some examples, a high-pass filter may be utilizedinstead of a bandpass filter 1602. FA high-pass filter may be used, forexample, where it is known that the target space to be imaged hasrelatively low levels of autofluorescent light and IR in the wavelengthsto be measured. The use of a high-pass filter may reduce system cost,for example, by reducing computational complexity and/or reducing thecost of sensor(s) 104 necessary for operation of the contaminationsensing device 100.

In some examples, the sensor(s) 104 may comprise a camera. In someexamples, the sensor(s) 104 may comprise an array of cameras. In someexamples, a bandpass or dual-bandpass filter may be coupled to a camerato allow only wavelengths inside the bandpass ranges to pass into thecamera. In some examples, each camera in an array of cameras may becorrespond to a different filter to block/reduce different wavelengths.In some examples where each camera is coupled to a different filter,photos taken by each camera may show the wavelengths of light remainingafter passing through the associated filter.

In some examples, a digital filter may be used instead of or in additionto physical filters. For example, the control system 610 may apply adigital filter to data provided by the sensor(s) 104. In some examples,the control system 610 may select from a number of programmed filtersthat may be, for example, high-pass filters, band-pass filters, and/orlow-pass filters. In some examples, the control system 610 may generateand or adjust filters to be applied to the data from the sensor(s) 104.In some examples, the control system 610 may use digital filters todetermine a contamination source. For example, a digital filter may beapplied to data collected by the contamination sensing device 100 todetermine if a target contamination source is present. In some examples,a digital filter may block/reduce wavelengths that are not known to beemitted from a target contamination source in response to excitationwavelengths. The digital filter, for example, may be used to determinethat the measured emission wavelength may correspond to a specificcontamination source. For example, contamination sources that containspyoverdine may emit wavelengths of approximately 430 nm and 530 nm. Todetermine if a contamination source comprises pyoverdine, the controlsystem 610 may, for example, use a digital filter to block/reducewavelengths outside of approximately 430 nm and 530 nm.

In some examples, the contamination sensing device 100 may access adatabase comprising excitation spectra and autofluorescence spectra(e.g., emission spectra). The database may comprise excitation spectraand autofluorescence spectra, for example, for microorganisms, bacteria,and/or other organic material. In some examples, the database maycomprise excitation spectra and autofluorescence spectra for surfacematerials which may comprise non-organic materials. In some examples,the database may comprise excitation spectra and autofluorescencespectra for cleaning products (e.g., cleaning product residue which maybe left on a surface). The contamination sensing device 100 may use theexcitation spectra and autofluorescence spectra from the database todetermine a source of a wavelength emitted following an emission ofexcitation light.

FIG. 17 is a flowchart showing an example workflow 1700 for measuringbacterial load. The contamination sensing device 100 may determine todetect contamination beginning at step 1702. The contamination sensingdevice 100 may optionally access a contamination excitation-emissiondatabase at step 1704. The database may comprise excitation spectra andautofluorescence spectra for various contamination sources (e.g.,bacteria). The database may comprise excitation and emission spectrathat indicate, for a particular contamination source, the excitationwavelength that causes the contamination source to autofluoresce. Insome examples, each type of contamination may have an associatedemission spectra and excitation spectra. The contamination sensingdevice 100 may determine, at step 1706, if the measurement is complete.In some examples, the measurement may be complete if the contaminationsensing device 100 took measurements for each contamination source inthe database (e.g., emitted light corresponding to the excitationwavelength of each contamination source and measured light in theemission/autofluorescence wavelengths the associated contaminationsource). In some examples, the contamination sensing device 100 may onlysearch for a portion of the contamination sources. For example, thecontamination sensing device 100 may only look for common contaminationsources, such as those corresponding to tryptophan and/or pyoverdine. Insome examples, the measurement may be complete if the contaminationsensing device 100 measures each emission wavelength at each excitationwavelength.

If the measurement is not complete (step 1706: NO), the contaminationsensing device 100 may emit an excitation light corresponding to aspecific contamination source at step 1708. If the contamination sourceis on the target surface, the contamination may autofluoresce inresponse to the excitation light. The contamination sensing device 100may measure light from the surface at step 1710. For example, thecontamination sensing device 100 may look for the emission wavelengthcorresponding to the contamination source at step 1708. In someexamples, the wavelength emitted at step 1708 may comprise a wavelengthor wavelength range of a number of predetermined wavelengths orwavelength ranges. The predetermined wavelengths or wavelength rangesmay be wavelengths known to initiate autofluorescence in a target (e.g.,contamination, bacteria, surface material, etc.). In some examples, thesensor(s) 104 may measure multiple light emission wavelengths at step1710. In some examples with multiple sensors (104), the contaminationsensing device 100 may measure multiple emission wavelengths in parallel(e.g., simultaneously). In some examples, the sensor(s) 104 may measuretwo or more wavelength ranges at once, such as, for example, by using adual bandpass or multi bandpass filter. In some examples, where eachsensor(s) 104 is associated with multiple filters, the contaminationsensing device 100 may repeat step 1710 for each filter. After measuringthe light emission from the surface, the contamination sensing device100 may return to step 1706 to determine if the measurement is complete.

If the measurement is not complete (step 1706: NO), steps 1706-1710 maybe repeated until all the contamination sources from the database havebeen tested (e.g., emitted the excitation wavelength and measured theemission wavelengths for each contamination source. In some examples,step 1708 and/or 1710 may be performed simultaneously by emittingmultiple excitation wavelengths and measuring multiple emissionwavelengths at approximately the same time. If the measurement iscomplete (e.g., all of the contamination sources have been tested or arequisite portion of the contamination sources have been tested) (step1706: YES), the bacterial load sensor reading may be complete at step1712. In some examples, the steps of workflow 1700 may be performeddifferent orders than shown. In some examples, steps 1706-1710 may beperformed using a programmed set of excitation and emission wavelengths,and step 1704 may be performed after steps 1706-1710 to process theresults of steps 1706-1710. In some examples, the measured emissionwavelengths and corresponding excitation wavelengths may be compared tothe contamination database after and/or during steps 1706-1710.

In some examples, the contamination sensing device 100 may requirecalibration before use and/or periodically after an initial calibration.In some examples, calibration sensor readings may be used to filter outbackground noise (e.g., ambient light and/or object fluorescence).Reference swatches may be used to allow intensity calibration to knownmicroorganism levels. For example, a plate of a known bacteria, bacteriatype, and/or CFU count may be used as a reference swatch. A measurementswatch (e.g., an object with known size) may be used to calibrate thetraditional visible light camera. Use of a measurement swatch may allowfor pictures to be correlated to actual locations and distances in thespace. In some examples, separating the background fluorescence from themicroorganism fluorescence may comprise measuring the fluorescence ofthe surface after sterilization and removal of the sterilizationproduct. The measurement after sterilization and removal of thesterilization product may be subtracted from the actual measurement(e.g., measurement of the surface and the bacterial load).

In some examples, for calibration, the contamination sensing device 100may take measurements of the target surface 210 at several differentexcitation wavelengths to determine one or more excitation wavelengthsthat do not cause fluorescence of the background surface/target surface210, but still cause fluorescence of at least some of themicroorganisms.

In some examples, algorithms may be used to reduce noise in an image.Noise may be reduced, for example, by subtracting a calibration imagefrom the captured image. In some examples, algorithms may be used tocomposite sensor data and camera data into a combined image. Data fromseveral devices/sensor nodes in a space may be stitched together to forman image that represents an entire area, room, or floor, for example, ofa building.

Computer vision algorithms may be used to check measurements for errorcaused by background noise. For example, if the majority of the surfacebeing measured uniformly fluoresces at a certain intensity and/orwavelength, it may be recognized that the surface is causing thisfluorescence, and the algorithm may flag the measurement for manualcheck. In some examples, an additional database of materials and/orobjects known to fluoresce may be stored. A computer vision algorithmmay identify the materials and/or objects observed in the image of thespace and compare them to the materials and/or objects in the database.Materials and/or objects that match in the database may then be maskedout of the fluorescence image so they do not interfere with bacterialload measurements.

The contamination sensing device 100 may take measurements periodicallyon a pre-programmed schedule, such as, for example, once per night oncelights in a space are off. In some examples, measurements may be takenonce each hour. In some examples, measurements may be taken once a day.In some examples, the user of the system may manually initiate ameasurement at any time. Manual initiation may be a useful feature inmany scenarios including, for example, if an outbreak has occurred in ahospital and certain surfaces need to be checked for surfacecontamination containing the pathogen. In some examples, newmeasurements may be used to update a previous contamination map 900. Insome examples, the contamination sensing device 100 may be used beforeand after a surface is disinfected, either through traditional cleaningmethods or disinfecting lighting, to determine the performance of thedisinfection. In some examples, the contamination sensing device 100 maybe integrated with an occupancy sensor(s) to detect the presence ofpeople in the room and initiate measurements when the room is notoccupied.

In some examples, a processor receiving data from the contaminationsensing device 100 may be able to graph an excitation-emission matrix(EEM). The EEM may show emission spectra as a function of excitationwavelength and create a three dimensional matrix ofexcitation-emission-intensity points, where, in some examples, thez-axis shows intensity.

In some examples, a projector or other device capable of projecting animage onto a surface may be used in communication with the contaminationsensing device 100. A projector may be integrated into the contaminationsensing device 100 or mounted separate from the contamination sensingdevice 100. The projector may be configured to project a contaminationmap 900 of a measured surface onto the measured surface to visualize thecontamination. The projected contamination map 900 may be used, forexample, to direct disinfecting efforts onto the surface or to preventusers from touching certain parts of the surface. Projecting thecontamination map 900 onto the measured surface may be a beneficialvisual technique for showing contamination of surfaces and provokingaction be taken (e.g., to disinfect the surface). In some examples, thecontamination map 900 may be projected in color. The projection mayinclude a key/legend 902 to allow the users to interpret thecontamination map 900. In some examples, the projection may be 3D toshow higher concentrations of bacteria of in certain areas. This may beobtained with a 3D or holographic projector and/or multiple projectors.The contamination map 900 shown in FIG. 9 may also show an example ofthe projection of a contamination map 900 as projected back onto themeasured surface 906.

In some examples, computer vision algorithms may be used to increase thereadability of the image. In some examples, computer vision algorithmsmay be used to inform a separate system (e.g., a disinfecting lightingsolution) of high risk areas. In some examples, a color filtering oredge detection algorithm may isolate the location of bacteria onsurfaces in a captured image. The computer vision algorithms maycalculate the real room locations of contamination and send thosecontamination locations to a disinfecting lighting system 1200. Thedisinfecting lighting system 1200 may, in response to the contaminationlocations, increase disinfection power in the space or zone. Forexample, the disinfecting lighting system 1200 may, in response to thecontamination locations, emit light comprising a wavelength in a rangeof 380 to 420 nm, e.g., 405 nm, that may reduce the presence ofcontamination such as bacteria. The disinfecting light may be directedto the contamination locations to reduce the contamination present. Insome examples, the disinfecting light system 1200 may, in response tothe contamination locations, increase the irradiance of the disinfectinglight at the contamination locations. The computer vision algorithms maycalculate the surface area of a target surface 210 and determine apercentage of the target surface that may be contaminated. This data(e.g., the percentage of the target surface 210 that may becontaminated) may be used to alert staff to the presence of abnormallyhigh bacteria concentrations if the bacteria concentrations are above athreshold (e.g., predetermined threshold).

The data collected by the sensor(s) 104 may include, for example, pixelcolors, intensities per wavelength range, and/or SPDs (e.g., intensityper wavelength over a range of wavelengths) for the area that wasmeasured. Pixel color may correspond to a specific wavelength or rangeof wavelengths. The specific wavelength or range of wavelengths may beused to determine a type of bacteria causing the fluorescence. Anintensity may be used to determine a level of bacterial load. Thecontamination map may show any output including types of bacteria andlevels of bacterial load. The contamination may be color coded to showthe aforementioned outputs.

FIG. 18 is a flowchart showing an example workflow 1800 for binarydetection of bacterial load with a camera based sensor. Binary thresholdbioburden level sorting may be performed using a camera sensor,beginning at step 1802. A processed fluorescence image 1804 may beseparated, using an algorithm, into red, green, and/or blue channels ofthe image at step 1806. Intensity threshold values 1808 for each pixelof the image may be compared, for each color, to a threshold value forthat color at step 1810. The comparing the intensity threshold value1808 to the threshold value for that color may be repeated for eachpixel. It may be determined if each pixel's intensity for the colorexceeds the threshold intensity for that color at step 1812. If thepixel's color does not exceed the color threshold (step 1812: NO), thepixel may be set to white at step 1814. Setting a pixel to white mayindicate that bacteria was not detected or that detected bacteria wasbelow a threshold. In some examples, colors other than white may be usedto indicate that bacteria was not detected. If the pixel's color doesexceed the color threshold (step 1812: YES), the pixel may be set toblack at step 1816. Setting a pixel to black may indicate that bacteriawas detected. In some examples, colors other than black may be used toindicate that bacteria was detected. After completing steps 1810-1816for each pixel, the bioburden binary level sorting may be complete atstep 1818.

FIG. 19 shows a flowchart showing an example workflow 1900 for binarythreshold bioburden level sorting with a photodiode sensor for detectingcontamination (e.g., bacteria). Binary threshold bioburden level sortingmay be performed using a photodiode sensor beginning at step 1902.Intensity threshold values 1908 and a processed fluorescence image 1904may be compared to a threshold value at step 1906. The intensitythreshold values may indicate the autofluorescence necessary to indicatethat a surface is contaminated. The intensity threshold values may beincreased/decreased to adjusted adjust the sensitivity of thecontamination sensing device 100. The comparing the intensity thresholdvalue to the threshold intensity value 1906 may be repeated for eachpixel. It may be determined if each pixel's intensity exceeds thethreshold intensity at step 1910. If the pixel's intensity does notexceed the intensity threshold (step 1910: NO), the pixel may be set towhite at step 1912. The pixel's intensity not exceeding the intensitythreshold at step 1910 indicates that the location corresponding to thatpixel is not contaminated. Setting a pixel to white may indicate to auser that bacteria was not detected at the location corresponding tothat pixel or that the not enough bacteria was detected to exceed theintensity threshold value 1908. If the pixel's intensity does exceed theintensity threshold (step 1910: YES), the pixel may be set to black atstep 1914. Setting a pixel to black may indicate that bacteria wasdetected (e.g., the level of bacteria represented by that pixel exceedsthe amount determined by the intensity threshold value 1908). Aftercompleting steps 1906-1914 for each pixel, the bioburden binary levelsorting may be complete at step 1916. The bioburden binary level sortingmay create an image using the black and white pixels assigned at steps1910-1914. The image may indicate to a user where contamination (e.g.,bacteria) is located. In some examples, the image may indicate to a userto provide disinfection (e.g., manual cleaning, disinfecting light,etc.).

In some examples, there may be a bacterial load threshold. Binarydetection may only indicate bacterial load in locations where thebacterial load surpasses the bacterial load threshold. In some examples,there may be a maximum allowed threshold of surface bacterial load. Insome examples, a user may be notified if the sensor(s) 104 detectslevels above the maximum allowed threshold of surface bacterial load.The user may be notified if the sensor(s) 104 detects levels above themaximum allowed threshold of surface bacterial load, for example, bygenerating a signal, sending a message to a user device, etc.

Measured bacterial load may be used by the control system 610 to drivedecision making of a processor and/or controller. Theprocessor/controller may be able to determine when a surface isconsidered contaminated based on the measured bacterial loadmeeting/exceeding a bacterial load threshold. Thecontamination/bacterial load level at which the surface is consideredcontaminated may be predetermined by the user or determined by theprocessor/controller based on measurement trends. Theprocessor/controller may be able to determine what parts of the surfaceare contaminated. Some levels of bacterial load may be considered safeand/or acceptable and not contaminated. The contamination map key 902may indicate the bacterial load at which the surface may be consideredcontaminated. In some examples, the contamination map may only showcontaminated areas. In some examples, the contamination map may showboth uncontaminated and contaminated levels of bacterial load.

In some examples, data obtained from the contamination sensing device100 may be used to produce information to display to a user. Acontamination map 900 showing the locations and concentration ofbacteria may be provided to the user and stored to show changes overtime. The contamination map 900 may be provided with a key 902 to helpthe user interpret it. The contamination map may be color coded to showconcentrations/intensities and/or changes in concentrations/intensitiesof bacteria. The contamination map 900 may be color coded (or otherforms of differentiating), to indicate different bins of bacteriadetected on the target surface 210. The example device may be able todetermine the types of bacteria in bins. This information may beprovided to the user.

FIG. 20 shows an example bioburden level sorting workflow 2000 in theform of a flow chart for a camera sensor. For example, the sensor(s) 104may be a camera. A camera may, in some examples, provide more detailedinformation about autofluorescent light detected than a photodiodesensor. The camera may produce an image containing separate red, green,and blue channels. Binning bacteria by emission color for a camerasensor may be performed, beginning at step 2002. A processedfluorescence image 2004 may be separated, using an algorithm, into red,green, and/or blue channels of the image at step 2006. In some examples,each pixel may be separated into subpixels at step 2006. In someexamples, each subpixel may represent red, green, or blue. Each channelmay comprise information indicating if contamination is present thatautofluoresces at an emission wavelength that corresponds to red, green,or blue.

A database of bacteria fluorescence emission colors may be used tocompare the color of each pixel (e.g., subpixel) or group (e.g., set,subset, etc.) of averaged pixels to the bacteria fluorescence emissioncolors from the database at step 2110. The database of bacteriafluorescence emission colors 2008 may indicate, for example, if acontamination source (e.g., bacteria) autofluoresces at wavelengths thatcorrespond to red, green, and/or blue. The pixels (e.g., subpixels) orgroup of averaged pixels may be sorted into groups of bacteria withsimilar emission colors at step 2012. For example, the red, green, andblue colors from the processed fluorescence image 2004 may match aspecific bacteria fluorescence emission color from the database 2008. Insome examples, a digital filter corresponding to the bacteriafluorescence emission colors from the database 2008 may be used at step2012 to sort the pixels. The digital filter may, for example, filter outpixels/subpixels that are not associated with the emission of a targetbacteria (e.g., contamination) from the database 2008. The digitalfilter may, for example, allow the contamination sensing device 100 toremove colors/wavelengths that are not associated with autofluorescencefrom a target contamination source. The matches from comparing at step2010 may be sorted at step 2012 into groups/sets of bacteria that emitsimilar emission colors. A report of possible bacteria types observed inthe fluorescence image, based on the sorted matches from step 2012, mayoptionally be output at step 2014. The report output at step 2014 mayindicate the bacteria shown by the processed fluorescence image 2004 tomatch the database of bacteria fluorescence emission colors 2008. Thebacteria observed by the camera sensor may be sorted by emission colorand completed at step 2016.

FIG. 21 shows an example bioburden level sorting workflow 2100 in theform of a flow chart for a multi-spectral/spectrometer based sensor.Multi-spectral/spectrometer based sensor may, for example, provide theentire emission wavelength of a surface measured by themulti-spectra/spectrometer sensors. Multi-spectral/spectrometer sensormay provide the more detailed wavelength information than photodiodesensors or camera sensors. Sorting bacteria by emission color for amulti-spectral/spectrometer sensor may be performed, beginning at step2102. Each pixel of the processed fluorescence image may comprise an SPDrepresenting the spectrum measured by the multi-spectral/spectrometersensors. The SPD of each pixel from a processed fluorescence image 2104may be compared with a database of bacteria fluorescence (e.g.,autofluorescence) emission spectra 2106 at step 2108. The database ofbacterial fluorescence emission spectra may indicate the emissionspectra (e.g., wavelengths) of various contamination sources. The pixelsmay be sorted into groups/sets of bacteria with similar emission SPDs atstep 2110. A report of possible bacteria types observed in thefluorescence image, based on the sorted matches from step 2110, mayoptionally be output at step 2112. The report output at step 2112 mayindicate the bacteria shown by the processed fluorescence image 2104 tomatch the database of bacteria fluorescence emission spectra 2106. Thebacteria observed by the multi-spectra/spectrometer sensor may be sortedby emission spectrum and completed at step 2114.

In some examples, the stored measurements from the contamination sensingdevice 100 may be used to provide a graph of reduction of bacteria overtime. In some examples, the system may be able to monitor the bacterialload of a space over time. This will allow the user to understandchanges and trends in bacterial load.

Changes in surface bacterial load may be determined, for example,through a measured change in surface area that the bacteria iscontaminating, and/or through the change in intensity of theautofluorescence measured by the sensor(s) 104 (e.g.,density/concentration of bacteria) over time. Reduction measurements maybe presented as a percent reduction (e.g., 50% reduction) from apredetermined or peak time measurement. In some examples, surfacebacterial load may be rated on a number scale. For example, anormal/average measurement may be taken and rated a ‘5’ on a ‘0-10’scale. Further bacterial load measurements may be compared to thisaverage value. A ‘7’ may indicate higher bacterial load than normal, a‘3’ may indicate a lower bacterial load than normal. In some examples, ameasurement may be taken after the surface is disinfected to determine arealistic minimum for bacterial load (e.g., for comparison).

The example device may be integrated into an internally illuminatedsurface, such as those described in U.S. application Ser. No. 16/000,426filed on Jun. 5, 2018, entitled “Devices Using Flexible Light EmittingLayer for Creating Disinfecting Illuminated Surface, and RelatedMethod,” which is hereby incorporated by reference herein in itsentirety. Such surfaces may be equipped with disinfecting lightsource(s) interior to the surface such that an outer exterior of thesurface is disinfected. The disinfecting light source(s) may emitdisinfecting light may comprising a wavelength in a range of 380 to 420nm, e.g., 405 nm. The disinfecting light may reduce the presence ofcontamination. The examples disclosed herein may be disposed within aninternally illuminated surface and configured to be facing the exteriorof the surface. Fluorescence may be measured through the surface so thatbacteria located on the exterior of the surface may be detected,measured, and/or characterized. The contamination sensing device 100 maycommunicate with and/or directly control the internally illuminatedsurface. The contamination sensing device 100, processor, and/or controlsystem 610 associated with the example device may perform functionscomprising turning the disinfecting light source(s) off when ameasurement is being taken by the example device and/or adjusting theintensity or color of the emitted light from the disinfecting lightsource(s).

In some examples, machine learning (e.g., deep learning, neuralnetworks, convolutional neural networks (CNN), etc.) may be used inconjunction with or instead of traditional computer vision algorithmsused to isolate fluorescence. A learning model may be used to train thecomputer to spot bacteria from fluorescence and differentiate frombackground noise. This may be done through training using labeledreference images or data with known amounts of fluorescence and/orbacteria. The trained model may then be applied to new images todetermine bacterial load.

The contamination sensing device 100 may be used in conjunction withcurrent/other methods of determining surface bacterial load, such asbacterial culture tests. The contamination sensing device 100 may directthe user performing the test to the optimal location for taking asurface sample.

In some examples, it may be understood that the physical contaminationsensing device 100 and the system in which the contamination sensingdevice 100 operates may be separate. The physical contamination sensingdevice 100 may comprise components including the excitation lightsource(s) 102 and sensor(s) 104 able to detect fluorescence. Additionalcomponents of the physical device may include distance sensor(s),occupancy sensor(s), timer(s), projector(s), and/or additionalcamera(s). The contamination sensing device 100 may include one ormultiple housings for these components. These components may bephysically coupled or separate. The contamination sensing device 100 mayinclude wired or wireless communication capabilities and a source ofpower. The system in which the contamination sensing device 100 mayoperate may include a computer processor able to process the datacollected by the contamination sensing device 100. The processor may beable to perform computer vision algorithms for detecting, measuring, andcharacterizing bacterial load. The system may be able to monitor changesin bacterial load over time. The system may include a user interface(e.g., a computer application) where the processed data from the exampledevice may be accessible by a user. The processed data may include acontamination map 900, levels of bacterial load, binary detection ofbacterial load and/or bacterial load, graphs and/or tables of change inbacterial load over time, types of bacteria detected on the surfacesorted into bins, etc. The system may include a disinfecting lightfixture 700. The disinfecting light fixture 700 may emit disinfectinglight may comprising a wavelength in a range of 380 to 420 nm, e.g., 405nm, and may reduce the presence of contamination such as bacteria. Thedisinfecting light fixture 700 may emit the disinfecting light, forexample, in response to the processed data indicating detectedcontamination on the surface. The system may include a control system610 able to make decisions and alter the operations of devices/sensorsin the space. The environment in which the example device and systemoperate may comprise an indoor and/or outdoor space with surfaces. Thepresent disclosure may comprise any of the aforementioned examples.

The contamination sensing devices 100 and systems described herein maybe implemented via a hardware platform such as, for example, the examplecomputing device 2200 illustrated in FIG. 22 . In some examples, thecomputing device 2200 may implement the flowcharts of FIGS. 8, 10, and17-21 . The contamination sensing devices 100 and systems describedherein may be separate components, may comprise separate components, ormay be incorporated into a single device. Some elements described withreference to the computing device 2200 may be alternately implemented insoftware. The computing device 2200 may include one or more processors2201, which may execute instructions of a computer program to performany of the features described herein. The instructions may be stored inany type of tangible computer-readable medium or memory, to configurethe operation of the processor 2201. As used herein, the term tangiblecomputer-readable storage medium is expressly defined to include storagedevices or storage discs and to exclude transmission media andpropagating signals. For example, instructions may be stored in aread-only memory (ROM) 2202, random access memory (RAM) 2203, removablemedia 2204, such as a Universal Serial Bus (USB) drive, compact disk(CD) or digital versatile disk (DVD), floppy disk drive, or any otherdesired electronic storage medium. Instructions may also be stored in anattached (or internal) hard drive 2205. The computing device 2200 mayinclude one or more input/output devices 2206, such as a display, touchscreen, keyboard, mouse, microphone, software user interface, etc. Thecomputing device 2200 may include one or more device controllers 2207such as a video processor, keyboard controller, etc. The computingdevice 2200 may also include one or more network interfaces 2208, suchas input/output circuits (such as a network card) to communicate with anetwork such as example network 106. The network interface 2208 may be awired interface, wireless interface, or a combination thereof. One ormore of the elements described above may be removed, rearranged, orsupplemented without departing from the scope of the present disclosure.

An example contamination sensing device may comprise a body, a lightemitter disposed on the body and configured to emit an excitationwavelength of light toward a surface, a sensor disposed on the body,configured to detect light, and directed toward the surface, and afilter adjuster configured to determine, based on the excitationwavelength of light, a filter configured to remove light outside of anemission wavelength range, wherein the emission wavelength rangecorresponds to wavelengths of light emitted by contamination uponexposure to the excitation wavelength of light, and adjustably move thefilter in front of the sensor.

In some examples, the excitation wavelength is within an excitationrange of 230-280 nm, and the emission wavelength range is 330-350 nm.

In some examples, the excitation wavelength is within an excitationrange of 385-405 nm, and the emission wavelength range is 430-530 nm.

In some examples, the sensor comprises a camera, photodiode, photodiodearray, or multi-spectral sensor.

In some examples, the sensor is configured to detect a distance betweenthe sensor and the surface, the light emitter is configured to adjust,based on the distance between the sensor and the surface, an intensityof the excitation wavelength of light, and the contamination sensingdevice further comprises a processor configured to determinecontamination on the surface, wherein the contamination is determinedbased on a wavelength of light detected by the sensor, an emissionintensity of the light detected by the sensor, and the intensity of theexcitation wavelength.

In some examples, the contamination sensing device further comprises aprocessor configured to determine, based on a database associatingexcitation spectra and emission spectra of microorganisms or surfacematerials, the excitation wavelength, determine, based on an emissionspectra associated with the determined excitation wavelength, theemission wavelength range, and configure the light emitter to emit theexcitation wavelength.

In some examples, the sensor comprises a camera and is furtherconfigured to capture an image of the surface, and the contaminationsensing device further comprises a processor configured to generate,based on the image and based on the sensor detecting light within theemission wavelength range, a contamination map.

In some examples, the light emitter comprises one of a light emittingdiode (LED), an array of LEDs, a laser, an array of lasers, a verticalcavity surface emitting laser (VCSEL), or an array of VCSELs.

In some examples, the contamination sensing device further comprises aprocessor configured to receive, from the sensor at a first time, afirst measurement of light from the surface, receive, from the sensor ata second time, a second measurement of light from the surface, anddetermine, based on the first measurement and the second measurement, achange in contamination of the surface.

In some examples, the contamination sensing device further comprises aprocessor configured to determine, based on a target contamination, adigital filter configured to remove light outside a filtered wavelengthrange, wherein the filtered wavelength range corresponds to wavelengthsof light emitted by the target contamination upon exposure to theexcitation wavelength, and apply the digital filter to light detected bythe sensor.

An example contamination sensing system may comprise a light emittingdevice configured to emit an excitation wavelength of light toward asurface, a light detecting device, in communication with the lightemitting device, comprising a sensor configured to detect light anddirected toward the surface, and a filter adjuster configured todetermine, based on the excitation wavelength of light, a filterconfigured to remove light outside of an emission wavelength range,wherein the emission wavelength range corresponds to wavelengths oflight emitted by contamination upon exposure to the excitationwavelength of light, and adjustably move the filter in front of thesensor.

In some examples, the excitation wavelength is within an excitationrange of 230-280 nm, and the emission wavelength range is 330-350 nm.

In some examples, the excitation wavelength is within an excitationrange of 385-405 nm, and the emission wavelength range is 430-530 nm.

In some examples, the contamination sensing system further comprises aprocessor configured to determine, based on a database associatingexcitation spectra and emission spectra of microorganisms or surfacematerials, the excitation wavelength, determine, based on an emissionspectra associated with the determined excitation wavelength, theemission wavelength range, and configure the light emitting device toemit the excitation wavelength.

In some examples, the contamination sensing system further comprises aprocessor configured to receive, from the sensor at a first time, afirst measurement of light from the surface, receive, from the sensor ata second time, a second measurement of light from the surface, anddetermine, based on the first measurement and the second measurement, achange in contamination of the surface.

In some examples, the contamination sensing system further comprises aprocessor configured to determine, based on a target contamination, adigital filter configured to remove light outside a filtered wavelengthrange, wherein the filtered wavelength range corresponds to wavelengthsof light emitted by the target contamination upon exposure to theexcitation wavelength, and apply the digital filter to light detected bythe sensor.

An example contamination sensing device may comprise a body, at leastone light emitter disposed on the body and configured to emit a lightcomprising an excitation wavelength toward a surface, and a plurality ofsensors disposed on the body and directed toward the surface, whereineach sensor of the plurality of sensors is configured to detect adifferent emission wavelength corresponding to respective wavelengths oflight emitted by contamination upon exposure to the emitted light.

In some examples, the at least one light emitter comprises an array oflight emitters, and the light comprises a plurality of differentexcitation wavelengths of light emitted by the respective emitters ofthe array of light emitters.

In some examples, the light emitted by the at least one light emittercomprises a plurality of excitation wavelengths.

In some examples, the contamination sensing device further comprises aplurality of filters, wherein each filter is associated with a differentsensor of the plurality of sensors, and wherein each sensor of theplurality of sensors is configured to detect the different emissionwavelength range based on the associated filter removing light outsideof the different emission wavelength ranges.

In some examples, each sensor of the plurality of sensors comprises acamera.

In some examples, the contamination sensing device further comprises aprocessor configured to determine, based on a target contamination, adigital filter configured to remove light outside a filtered wavelengthrange, wherein the filtered wavelength range corresponds to wavelengthsof light emitted by the target contamination upon exposure to theexcitation wavelength, and apply the digital filter to light detected bythe sensor 23.

In some examples, wherein the plurality of sensors is a first pluralityof sensors, the contamination sensing device further comprises one ormore groups of sensors, wherein each group of the one or more groups ofsensors comprises at least one first sensor from the first plurality ofsensors and at least one second sensor from a second plurality ofsensors, and wherein the at least one first sensor and the at least onesecond sensor detect a same emission wavelength.

The above discussed embodiments are simply examples, and modificationsmay be made as desired for different implementations. For example, stepsand/or components may be subdivided, combined, rearranged, removed,and/or augmented; performed on a single device or a plurality ofdevices; performed in parallel, in series; or any combination thereof.Additional features may be added.

We claim:
 1. A contamination sensing device comprising: a body; at leastone light emitter disposed on the body and configured to emit a lightcomprising an excitation wavelength toward a surface; and a plurality ofsensors disposed on the body and directed toward the surface; whereineach sensor of the plurality of sensors is configured to detect adifferent emission wavelength range corresponding to respectivewavelengths of light emitted by contamination upon exposure to theemitted light, and wherein at least one sensor of the plurality ofsensors is configured to detect a concentration level of thecontamination, and wherein at least one sensor of the plurality ofsensors comprises a camera and is further configured to capture an imageof the surface, the contamination sensing device further comprising oneor more processors configured to generate, based on the image and basedon the at least one sensor detecting light within an emission wavelengthrange, and based on the at least one sensor of the plurality of sensorsdetecting the concentration level of the contamination, a contaminationmap.
 2. The contamination sensing device of claim 1, wherein: the atleast one light emitter comprises an array of light emitters; and thelight comprises a plurality of different excitation wavelengths of lightemitted by the respective emitters of the array of light emitters. 3.The contamination sensing device of claim 1, wherein the light emittedby the at least one light emitter comprises a plurality of excitationwavelengths.
 4. The contamination sensing device of claim 1, furthercomprising: a plurality of filters, wherein each filter is associatedwith a different sensor of the plurality of sensors, and wherein eachsensor of the plurality of sensors is configured to detect the differentemission wavelength range based on the associated filter removing lightoutside of the different emission wavelength range.
 5. The contaminationsensing device of claim 1, wherein at least one sensor of the pluralityof sensors comprises a camera, a photodiode, a photodiode array, or amulti-spectral sensor.
 6. The contamination sensing device of claim 1,wherein the one or more processors are further configured to: determine,based on a target contamination, a digital filter configured to removelight outside a filtered wavelength range, wherein the filteredwavelength range corresponds to wavelengths of light emitted by thetarget contamination upon exposure to the excitation wavelength; andapply the digital filter to light detected by at least one sensor of theplurality of sensors.
 7. The contamination sensing device of claim 1,wherein the plurality of sensors is a first plurality of sensors, thecontamination sensing device further comprising one or more groups ofsensors, wherein each group of the one or more groups of sensorscomprises at least one first sensor from the first plurality of sensorsand at least one second sensor from a second plurality of sensors, andwherein the at least one first sensor and the at least one second sensordetect a same emission wavelength.
 8. The contamination sensing deviceof claim 1, wherein: the excitation wavelength is within an excitationrange of 200-350 nanometers (nm); and at least one sensor of theplurality of sensors is configured to detect an emission wavelengthwithin an emission wavelength range of 330-350 nm.
 9. The contaminationsensing device of claim 1, wherein: the excitation wavelength is withinan excitation range of 385-405 nanometers (nm); and at least one sensorof the plurality of sensors is configured to detect an emissionwavelength within an emission wavelength range of 430-530 nm.
 10. Thecontamination sensing device of claim 1, wherein at least one sensor ofthe plurality of sensors is configured to detect a distance between theat least one sensor and the surface, and wherein the at least one lightemitter is configured to adjust, based on the distance between the atleast one sensor and the surface, an intensity of the excitationwavelength of the light, wherein the one or more processors are furtherconfigured to determine contamination on the surface, wherein thecontamination is determined based on: a wavelength of light detected bythe at least one sensor, an emission intensity of the light detected bythe at least one sensor, and the intensity of the excitation wavelength.11. The contamination sensing device of claim 1, wherein the one or moreprocessors are further configured to: determine, based on a databaseassociating excitation spectra and emission spectra of microorganisms orsurface materials, the excitation wavelength; determine, based on anemission spectra associated with the determined excitation wavelength,emission wavelength ranges; and configure the at least one light emitterto emit the excitation wavelength.
 12. The contamination sensing deviceof claim 1, wherein the at least one light emitter comprises one of alight emitting diode (LED), an array of LEDs, a laser, an array oflasers, a vertical cavity surface emitting laser (VCSEL), or an array ofVCSELs.
 13. The contamination sensing device of claim 1, wherein the oneor more processors are further configured to: receive, from at least onesensor of the plurality of sensors at a first time, a first measurementof light from the surface; receive, from the at least one sensor at asecond time, a second measurement of light from the surface; anddetermine, based on the first measurement and the second measurement, achange in contamination of the surface.
 14. The contamination sensingdevice of claim 1, wherein the one or more processors are furtherconfigured to: receive, from at least one sensor of the plurality ofsensors, a measurement of light from the surface; and determine, basedon the measurement, the contamination on the surface.
 15. Thecontamination sensing device of claim 1, wherein the one or moreprocessors are further configured to: determine, based on a targetcontamination, a digital filter configured to remove light outside afiltered wavelength range, wherein the filtered wavelength rangecorresponds to wavelengths of light emitted by the target contaminationupon exposure to the excitation wavelength; and apply the digital filterto light detected by the plurality of sensors.
 16. The contaminationsensing device of claim 1, wherein the generated contamination mapcomprises colors indicating the contamination.
 17. The contaminationsensing device of claim 1, wherein the one or more processors and adisinfecting lighting system are configured to: turn off the at leastone light emitter; determine, from at least one sensor of the pluralityof sensors, a contamination on the surface in the dark; and adjust awavelength of disinfecting light emitted, an irradiance of thedisinfecting light emitted, and an amount of time the disinfecting lightis emitted from the disinfecting lighting system.
 18. A contaminationsensing system comprising: a light emitting device configured to emit alight comprising an excitation wavelength toward a surface; and a lightdetecting device, in communication with the light emitting device,comprising a plurality of sensors directed towards the surface, whereineach sensor of the plurality of sensors is configured to detect adifferent emission wavelength corresponding to respective wavelengths oflight emitted by contamination upon exposure to the emitted light, andwherein at least one sensor of the plurality of sensors is configured todetect a concentration level of the contamination, wherein at least onesensor of the plurality of sensors comprises a camera configured tocapture an image of the surface, the contamination sensing devicefurther comprising one or more processors configured to generate, basedon the image and based on the at least one sensor detecting light withinan emission wavelength range, and based on the at least one sensor ofthe plurality of sensors detecting the concentration level of thecontamination, a contamination map.
 19. The contamination sensing systemof claim 18, wherein at least one sensor of the plurality of sensorscomprises a camera, a photodiode, a photodiode array, or amulti-spectral sensor.
 20. The contamination sensing system of claim 18,wherein the light emitting device comprises at least one of a lightemitting diode (LED), an array of LEDs, a laser, an array of lasers, avertical cavity surface emitting laser (VCSEL), or an array of VCSELs.21. The contamination sensing system of claim 18, further comprising: aplurality of filters, wherein each filter is associated with a differentsensor of the plurality of sensors, and wherein each sensor of theplurality of sensors is configured to detect the different emissionwavelength range based on the associated filter removing light outsideof the different emission wavelength range.
 22. The contaminationsensing system of claim 18, wherein the one or more processors arefurther configured to: determine, based on a target contamination, adigital filter configured to remove light outside a filtered wavelengthrange, wherein the filtered wavelength range corresponds to wavelengthsof light emitted by the target contamination upon exposure to theexcitation wavelength; and apply the digital filter to light detected byat least one sensor of the plurality of sensors.
 23. The contaminationsensing system of claim 18, wherein: the excitation wavelength is withinan excitation range of 200-350 nanometers (nm) or 385-405 nm; at leastone first sensor of the plurality of sensors is configured to detect anemission wavelength within an emission wavelength range of 330-350 nm;and at least one second sensor of the plurality of sensors is configuredto detect an emission wavelength within an emission wavelength range of430-530 nm.
 24. The contamination sensing system of claim 18, whereinthe one or more processors are further configured to: receive, from atleast one sensor of the plurality of sensors, a measurement of lightfrom the surface; and determine, based on the measurement, thecontamination on the surface.
 25. The contamination sensing system ofclaim 18, wherein the one or more processors and a disinfecting lightingsystem are configured to: turn off the at least one light emitter;determine, from at least one sensor of the plurality of sensors, acontamination on the surface in the dark; and adjust a wavelength ofdisinfecting light emitted, an irradiance of the disinfecting lightemitted, and an amount of time the disinfecting light is emitted fromthe disinfecting lighting system.
 26. The contamination sensing deviceof claim 18, wherein the generated contamination map comprises colorsindicating the contamination.